Pacemakers · Dual Chamber Temporary Pacemaker family

Medtronic 5388: troubleshooting and error codes

The ServiceForge knowledge base holds 57 documented symptoms for the Medtronic 5388, with 66 ranked causes, 115 diagnostic checks with test points and expected values, and 5 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Pacing lead system connection error patient safety

Incorrect or incomplete connection of pacing leads to patient cable receptacles, potentially resulting in no pacing or sensing in one or both chambers

Ranked causes

1. Bipolar lead system polarity reversed or incorrectly positioned (common)
2. Unipolar single chamber lead not connected to negative receptacle or indifferent electrode not in positive receptacle (occasional)
3. Unipolar dual chamber system missing jumper cable connection to indifferent electrode (common)
4. Lead connector pins loose or not fully inserted into cable receptacles (occasional)

First check

Visually inspect lead connector pins for visible signs of wear or damage

Test point: Lead connectors
Expected: No visible wear, damage, bending, or corrosion

5 more checks with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Pacemaker block point reached during rate adjustment patient safety

Device prevents further adjustment in the conflicting direction and displays warning message 'Pacemaker block point reached. Adjust RATE or parameters on Menu 2.' when user tries to set rate-dependent parameters to values that violate timing rules.

Ranked causes

1. RATE set higher than UPPER RATE (common)
2. A-V INTERVAL + 180 ms exceeds UPPER RATE interval (DVI mode) (occasional)
3. TARP (SAV Interval + PVARP) exceeds UPPER RATE interval (occasional)

First check

Verify RATE versus UPPER RATE relationship

Test point: Menu 2 RATE and UPPER RATE settings
Expected: RATE ≤ UPPER RATE

2 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Configure Atrial Tracking patient safety

Enable or disable atrial tracking between DDD and DDI modes via Menu 1 setting.

Ranked causes

1. A TRACKING set to OFF for DDI mode (common)
2. A TRACKING set to ON for DDD mode (common)

First check

Verify atrial tracking status

Test point: Menu 1 A TRACKING indicator
Expected: ON or OFF as selected

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Loss of ventricular capture patient safety

ECG shows no heart response after pacing pulse; heart does not contract and pump blood

Ranked causes

1. Stimulation threshold not properly set (common)
2. OUTPUT set too low (insufficient safety margin) (common)

First check

Verify RATE setting for stimulation threshold finding

Test point: RATE dial
Expected: At least 10 ppm above patient's intrinsic rate

3 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Power-on self-test failure - error code 0004

Model 5388 fails self-test with error 0004; typically caused by key press during self-test startup sequence

Ranked causes

1. Key pressed during power-on self-test sequence (common)
2. Key stuck in pressed position (occasional)

First check

Remove and re-insert battery to initiate fresh self-test

Test point: Power source
Expected: Device powers on and begins 4-second self-test sequence

1 more check with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Undersensing detected patient safety

Pacemaker does not detect intrinsic heart activity and paces on or between beats, competitive pacing risk

Ranked causes

1. Sensing threshold not properly established (common)
2. SENSITIVITY set too high (insufficient margin) (common)

First check

Verify RATE setting relative to patient intrinsic rate

Test point: RATE dial
Expected: At least 10 ppm below patient's intrinsic rate for sensing threshold procedure

2 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Adjust RAP rate or atrial output during delivery patient safety

Operator can modify pacing parameters while SELECT key is held and RAP is active

Ranked causes

1. Need to modify parameters during active RAP delivery (occasional)

First check

Maintain SELECT key pressed

Test point: SELECT key state
Expected: Key held down continuously

2 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Asynchronous pacing causes tachyarrhythmia risk patient safety

Device set to asynchronous (non-sensing) mode without inhibition of pacing during intrinsic activity

Ranked causes

1. Asynchronous pacing mode active with sensing disabled in one or both chambers (occasional)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Atrial rate not within tolerance patient safety

Measured atrial pulse interval outside specified range when set to target pacing rate

Ranked causes

1. Rate calibration drift or incorrect output setting (unknown)

First check

Measure atrial pulse interval at 30 ppm setting

Test point: atrial output
Expected: 1900-2100 ms, +/- 5%
Tools: digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Atrial rate out of specification patient safety

Measured atrial pulse interval does not fall within specified tolerance when set to designated rate in AAI mode

Ranked causes

1. Rate control adjustment incorrect or device malfunction (unknown)

First check

Measure atrial pulse interval at 30 ppm setting

Test point: Atrial output
Expected: 1900-2100 ms, +/- 5%
Tools: Digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Atrial rate out of tolerance

Measured atrial pulse interval does not fall within specified tolerance range when AAI mode is set

Ranked causes

1. Rate control adjustment incorrect (common)

First check

Verify atrial pulse interval at 30 ppm setting

Test point: Atrial output
Expected: 1900-2100 ms, +/- 5%
Tools: Digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Atrial rate pulse intervals out of tolerance patient safety

Measured atrial pulse interval does not match specified tolerance when set to a defined rate (30, 80, 120, or 200 ppm) in AAI mode.

Ranked causes

1. Rate control parameter not set correctly (common)

First check

Measure atrial pulse interval using digital counter

Test point: Atrial output
Expected: 30 ppm: 1900–2100 ms; 80 ppm: 712–788 ms; 120 ppm: 475–525 ms; 200 ppm: 285–315 ms, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Atrial refractory period not functioning patient safety

Atrial sense light behavior incorrect during refractory period testing; squarewaves within refractory window should not trigger sensing.

Ranked causes

1. ATR REFRACTORY setting incorrect or device malfunction (unknown)

First check

Verify signal generator square-wave amplitude across atrial load resistor

Test point: 500 ohm atrial load resistor
Expected: 20 mV, as measured
Tools: Signal generator, voltage measurement device

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Cable disconnection from pacemaker caution

Need to disconnect patient cable from Model 5388 pacemaker device

Ranked causes

1. Planned disconnection or cable replacement needed (unknown)

First check

Locate connector release button on patient cable plug

Test point: Patient cable plug connector
Expected: Release button clearly visible and accessible

2 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Cables not connecting to device patient safety

Surgical cables (Model 5832 or 5433 series) cannot be properly inserted into the atrial or ventricular sockets at the top of the device.

Ranked causes

1. Connector not aligned with correct socket (A for atrium, V for ventricle) (common)

First check

Verify cable model matches device compatibility

Test point: Cable connector and device socket
Expected: Model 5832 or Model 5433A/5433V cable

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Atrial current output patient safety

Verify atrial output amplitude at mid-width point of pulse meets specified range for three output levels: 0.2 mA, 5.0 mA, 20.0 mA

Ranked causes

1. Device output requires calibration verification (unknown)

First check

Measure atrial output amplitude at 0.2 mA setting

Test point: atrial load terminals
Expected: 0.1-0.3 mA, +/- 0.1 mA
Tools: oscilloscope, 500 ohm resistor

2 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: DC leakage (device off) patient safety

Verify DC leakage across atrial and ventricular load resistors when device is powered off

Ranked causes

1. DC leakage must be verified when device is off (unknown)

First check

Measure DC voltage across atrial load resistor (device off)

Test point: atrial load terminals
Expected: 10 uA Max (5 mV across 500 ohms)
Tools: DC voltmeter or oscilloscope, 500 ohm resistor

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Mode switching parameter retention patient safety

Verify that OUTPUT, SENSITIVITY, INTERVAL, and RATE parameters are retained or reset appropriately when switching pacing modes.

Ranked causes

1. Parameter retention rules during mode change (common)

First check

Confirm OUTPUT settings retained or reset

Test point: Upper OUTPUT dial
Expected: A OUTPUT retained if mode has atrial pacing; V OUTPUT nominal if newly added

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Pulse width patient safety

Procedure to verify atrial and ventricular pulse width output is correct using time interval measurement.

Ranked causes

1. Pulse width calibration required (unknown)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Deliver rapid atrial pacing (RAP) patient safety

LED flashes during RAP pulse delivery; pacing begins at displayed RAP rate with no ventricular support during A OUTPUT

Ranked causes

1. Operator procedure to initiate RAP burst (unknown)

First check

Verify atrial lead connectivity

Test point: atrial channel connection
Expected: leads in contact with atrium

3 more checks with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Device fails power-on self-test patient safety

Device remains on but does not pace after ON key pressed; self-test lasts ~4 seconds

Ranked causes

1. Internal hardware or firmware failure detected during self-test (unknown)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Device replacement after battery removal patient safety

Pacing maintained for 15 seconds after battery removal at 70 ppm and nominal outputs

Ranked causes

1. Battery removal during operation (rare)

First check

Confirm pacing continues after battery removal

Test point: device output
Expected: pacing continues for 15 seconds typical at 70 ppm nominal outputs

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Device turned on during lead connection setup high voltage

Model 5388 is powered on and operating while lead system is being connected to device cables.

Ranked causes

1. Device powered on before lead system connection completed (common)

First check

Verify device power state

Test point: Device power indicator or display
Expected: Device powered OFF

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Dial adjustment attempt while parameters locked triggers display indication

Turning upper screen dials while locked causes backlight to illuminate, padlock and flashing padlock icons appear in center of upper screen, lower screen displays message.

Ranked causes

1. User attempted to adjust locked parameters (common)

First check

Verify padlock and flashing padlock icons appear in center of upper screen

Test point: Upper screen display center
Expected: Padlock [ ] and flashing [ ] icons visible in center

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Emergency temporary pacing connection setup patient safety

Temporary pacing leads or heartwires must be connected directly to device sockets without standard surgical cables.

Ranked causes

1. Standard surgical cables unavailable; emergency procedure required (rare)

First check

Locate emergency connection sockets

Test point: Top end of device, four smaller sockets
Expected: Two sockets for atrium, two for ventricle visible and accessible

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Excessive current drain when device off

Device draws more than specified off-state current, indicating potential battery drain issue

Ranked causes

1. Internal battery drain or leakage (unknown)

First check

Measure device current draw with power off

Test point: Battery contacts via special fixture
Expected: no more than 150 uA
Tools: Analog milliammeter, battery simulator fixture

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Excessive current drain when device on

Device draws more than specified on-state current after 5 minutes with backlight off

Ranked causes

1. Internal power consumption exceeding specification (unknown)

First check

Measure device current draw 5 minutes after power on with backlight off

Test point: Battery contacts via special fixture
Expected: no more than 3.0 mA
Tools: Analog milliammeter, battery simulator fixture

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Insufficient current draw with backlight and menu on

Device current draw does not reach minimum specified level when backlight and menu are enabled

Ranked causes

1. Backlight or display circuit malfunction (unknown)

First check

Measure device current draw with backlight and menu on

Test point: Battery contacts via special fixture
Expected: at least 20.0 mA
Tools: Analog milliammeter, battery simulator fixture

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Low battery indicator appears patient safety

Low battery indicator appears during device operation

Ranked causes

1. Battery depleted (common)

First check

Visual confirmation of low battery indicator

Test point: device display
Expected: low battery indicator appears

5 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Low battery indicator displays during initialization

Low battery warning appears on display during screen initialization; does not indicate actual low battery unless backlight fails to activate

Ranked causes

1. Low battery indicator false positive during startup (common)

First check

Verify backlight activation during normal operation

Test point: Display backlight
Expected: Backlight activates normally; low battery indicator disappears

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Low battery voltage at power-on patient safety

Battery indicator appears and backlights do not turn on when ON key pressed

Ranked causes

1. Battery voltage insufficient for normal operation (common)

First check

Verify battery indicator presence on display

Test point: Lower display screen
Expected: Battery indicator symbol visible

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Pulse width measurement required

Verification of pacing pulse width at atrial and ventricular outputs

Ranked causes

1. Pulse width verification procedure (unknown)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Pulse width out of specification patient safety

Measured atrial or ventricular output pulse width does not meet specification

Ranked causes

1. Pulse width circuit malfunction or component drift (unknown)

First check

Measure atrial output pulse width

Test point: Atrial output
Expected: As specified in device documentation
Tools: Digital counter or oscilloscope at 0.2 ms/division

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Pulse width out of tolerance patient safety

Measured pulse width does not match specification when tested at the half-peak point.

Ranked causes

1. Pulse width control not set correctly (unknown)

First check

Measure pulse width from positive to negative half-peak point

Test point: Output pulse (atrial and/or ventricular)
Expected: As specified in pacemaker documentation (not provided in this section)
Tools: Digital counter or oscilloscope (0.2 ms/division)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

RAP rate out of tolerance patient safety

Rapid Atrial Pacing rate measured outside 350 ppm tolerance range

Ranked causes

1. RAP rate control setting incorrect (common)

First check

Verify RAP rate is 350 ppm +/- 5%

Test point: Atrial Pace LED output
Expected: 163-180 ms pulse interval, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rapid Atrial Pacing (RAP) rate not within tolerance patient safety

Measured atrial pacing rate during RAP mode outside specified range; A Pace LED may not flash at correct rate or V Pace LED continues flashing

Ranked causes

1. RAP mode not properly activated or rate drift (unknown)

First check

Verify RAP mode selection and LED indication

Test point: A Pace LED, V Pace LED
Expected: A Pace LED flashing at RAP rate; V Pace LED stopped

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rapid Atrial Pacing (RAP) rate out of specification patient safety

RAP mode atrial rate does not fall within 350 ppm +/- 5% (163-180 ms pulse interval) when RAP is activated

Ranked causes

1. RAP rate circuit malfunction or calibration error (unknown)

First check

Measure atrial pulse interval in RAP mode at 350 ppm setting

Test point: Atrial output
Expected: 163-180 ms, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rapid Atrial Pacing (RAP) rate out of tolerance patient safety

Measured atrial pacing rate does not match 350 ppm ±5% (163–180 ms) when RAP mode is activated.

Ranked causes

1. RAP rate parameter not set correctly (common)

First check

Verify atrial rate during RAP activation

Test point: Atrial output (A Pace LED)
Expected: 350 ppm +/- 5% (163–180 ms); A Pace LED flashes at RAP rate; V Pace LED stops flashing, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rapid atrial pacing rate out of specification patient safety

RAP mode delivers atrial pacing at rate outside 350 ppm tolerance when activated

Ranked causes

1. RAP mode rate control malfunction (unknown)

First check

Verify RAP mode pulse interval within tolerance

Test point: Atrial output
Expected: 163-180 ms, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rapid atrial pacing rate out of tolerance patient safety

RAP rate measured on counter does not fall within 350 ppm +/- 5% when RAP mode is selected and Select Key is held

Ranked causes

1. RAP mode rate control miscalibration (unknown)

First check

Measure atrial rate during RAP delivery

Test point: Atrial pace output
Expected: 350 ppm +/- 5% (163-180 ms), +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Rate-dependent parameter mismatch on mode change patient safety

During a mode change, if one or more manually set rate-dependent parameters in the previous mode will cause improper pacing in the new mode, the device automatically changes the parameter to its automatic, rate-dependent setting.

Ranked causes

1. Manually set rate-dependent parameter incompatible with new mode (common)

First check

Confirm parameter auto-adjustment after mode change

Test point: Menu 2 rate-dependent parameter values
Expected: Parameters set to automatic or mode-compatible values

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Refractory period test setup patient safety

Verification that pacemaker correctly inhibits sensing during refractory period and resumes sensing outside refractory period using delayed pulse injection

Ranked causes

1. Refractory period timing requires validation with dual-pulse sensing test (common)

First check

Atrial first sensing pulse response (in refractory period)

Test point: Pacemaker sensing input
Expected: No detection, output pulse present ms, ±1 ms
Tools: Oscilloscope, signal generator

3 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Resume pacing at upper screen settings after RAP patient safety

Return device to normal pacing operation after RAP burst completion

Ranked causes

1. RAP burst delivery complete; need to return to standard pacing (common)

First check

Release SELECT key to terminate RAP

Test point: SELECT key
Expected: Key released; pacing resumes at upper screen rate/output settings

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

SELECT key stuck - menu advance failure

SELECT key stuck; MENU key press will not advance menus; device does not respond to menu navigation

Ranked causes

1. SELECT key stuck mechanically during menu operation (rare)

First check

Press MENU key and observe menu advance

Test point: MENU key and menu display
Expected: MENU press advances to next menu screen

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Select pacing mode patient safety

Configure Medtronic 5388 temporary pacemaker to single-chamber (AOO, VOO, AAI, VVI) or dual-chamber (DDD, DDI, DVI, DOO) mode using OUTPUT and SENSITIVITY dials and MENU selections.

Ranked causes

1. Select via Dial-A-Mode menu (common)

First check

Verify pacing mode activated

Test point: Menu M display
Expected: Selected pacing mode underlined and activated

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Self-test completion and normal operation

Normal power-on self-test sequence: 4-second initialization, PACE and SENSE LEDs flash, sensing begins after completion

Ranked causes

1. Normal startup sequence verification (common)

First check

Verify power-on initiates self-test sequence

Test point: Device power and LED indicators
Expected: Device powered on; self-test active for approximately 4 seconds; PACE and SENSE LEDs light sequentially

2 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Self-test failure - PACE or SENSE LED remains on patient safety

Device fails self-test; one PACE or SENSE LED remains on continuously with no output pulses; failure code displayed

Ranked causes

1. Device hardware or firmware self-test failure (rare)

First check

Observe which LED remains illuminated

Test point: PACE or SENSE LED
Expected: LED turns off upon successful self-test completion

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Set sensitivity safety margin patient safety

Configure sensitivity to provide at least 2:1 safety margin; set to at least one-half to one-third the sensing threshold value

Ranked causes

1. Lead maturation and drug therapy affect threshold over time (common)

First check

Measure atrial or ventricular sensing threshold per protocol

Test point: A SENSITIVITY or V SENSITIVITY parameter
Expected: Threshold value in mV determined by decreasing sensitivity until sensing lost

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Unable to disconnect cable from device caution

Cable cannot be removed from the device socket after insertion.

Ranked causes

1. Connector release button not pressed before removal attempt (common)

First check

Locate connector release button on cable

Test point: Cable connector body
Expected: Release button present and accessible

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Upper dials locked during adjustment attempt

Upper dials do not turn and padlock icon appears on screen; backlights turn off

Ranked causes

1. Automatic lock activated after 60 seconds of inactivity or manual lock applied (common)

First check

Verify padlock icon on middle of screen

Test point: Display screen center
Expected: Padlock icon and flashing key icon visible when locked

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Upper screen parameters locked unintentionally

Turning upper screen dials does not change RATE, A OUTPUT, or V OUTPUT values; padlock icon appears in upper right corner; backlight turns off.

Ranked causes

1. Lock feature activated after 60 seconds of inactivity or lock key pressed (common)

First check

Verify padlock icon is displayed in upper right corner of upper screen

Test point: Upper screen display
Expected: Padlock [ ] icon visible in upper right corner

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular rate not within tolerance patient safety

Measured ventricular pulse interval outside specified range when set to target pacing rate

Ranked causes

1. Rate calibration drift or incorrect output setting (unknown)

First check

Measure ventricular pulse interval at 30 ppm setting

Test point: ventricular output
Expected: 1900-2100 ms, +/- 5%
Tools: digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular rate out of specification patient safety

Measured ventricular pulse interval does not fall within specified tolerance when set to designated rate in VVI mode

Ranked causes

1. Rate control adjustment incorrect or device malfunction (unknown)

First check

Measure ventricular pulse interval at 30 ppm setting

Test point: Ventricular output
Expected: 1900-2100 ms, +/- 5%
Tools: Digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular rate out of tolerance

Measured ventricular pulse interval does not fall within specified tolerance range when VVI mode is set

Ranked causes

1. Rate control adjustment incorrect (common)

First check

Verify ventricular pulse interval at 30 ppm setting

Test point: Ventricular output
Expected: 1900-2100 ms, +/- 5%
Tools: Digital counter

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular rate pulse intervals out of tolerance patient safety

Measured ventricular pulse interval does not match specified tolerance when set to a defined rate (30, 80, 120, or 200 ppm) in VVI mode.

Ranked causes

1. Rate control parameter not set correctly (common)

First check

Measure ventricular pulse interval using digital counter

Test point: Ventricular output
Expected: 30 ppm: 1900–2100 ms; 80 ppm: 712–788 ms; 120 ppm: 475–525 ms; 200 ppm: 285–315 ms, +/- 5%
Tools: Digital counter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular refractory period not functioning patient safety

Ventricular sense light behavior incorrect during refractory period testing; squarewaves within refractory window should not trigger sensing.

Ranked causes

1. VEN REFRACTORY setting incorrect or device malfunction (unknown)

First check

Verify signal generator square-wave amplitude across atrial load resistor

Test point: 500 ohm atrial load resistor
Expected: 20 mV, as measured
Tools: Signal generator, voltage measurement device

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventricular refractory period test patient safety

Verify that ventricular sensing respects the refractory period; input during refractory should not trigger ventricular sense light.

Ranked causes

1. Ventricular refractory period malfunction (unknown)

First check

Apply first squarewave input 220 ms after pacemaker output using switch position 1

Test point: ventricular input
Expected: Ventricular sense light should not come on mV, as measured across 500 ohm load
Tools: Signal generator, 500 ohm ventricular load resistor, switch position 1

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Error codes

Code	Meaning	Trigger	Severity
`0004`	Key stuck or key press during self-test	Key pressed while self-test is in process	error
`0004`	Power-on self-test failure caused by key press	User presses key while self-test in progress (first 4 seconds after power-on)	error
`Pacemaker block point reached`	Device has reached a timing constraint limit and cannot proceed with the requested adjustment	User attempts to set rate-dependent parameters to values that violate timing rules or set RATE higher than UPPER RATE	warning
`RATE cannot exceed UPPER RATE`	Attempted RATE adjustment exceeds the configured UPPER RATE limit	User attempts to set RATE higher than UPPER RATE	warning
`Timing Violation warning`	Rate-dependent parameter adjustment would exceed safe timing constraints	RATE adjustment would conflict with UPPER RATE PVARP or A-V INTERVAL limits	warning

Likely causes and actions for each code are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.