Tourniquet systems

Zimmer Biomet A.T.S. 750: troubleshooting and error codes

The ServiceForge knowledge base holds 25 documented symptoms for the Zimmer Biomet A.T.S. 750, with 37 ranked causes, 37 diagnostic checks with test points and expected values, and 18 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Cuff pressure above set point caution

Pressure display shows HI-P; pressure in cuff is 15 mmHg above set point

Ranked causes

1. Transient patient movement (occasional)
2. Controller overshoot (occasional)
3. Hose occlusion (occasional)
4. Hardware failure (rare)

First check

Observe pressure stability

Test point: PRESSURE display
Expected: Pressure returns to set point within seconds

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

AC power indicator does not illuminate

AC INDICATOR light remains dark when unit is plugged into power source

Ranked causes

1. Unit not plugged into power source (common)
2. Blown fuse in unit (occasional)
3. Power entry module or internal circuit failure (rare)

First check

Verify power cord is fully inserted into power entry module

Test point: Power entry module connection on back of unit
Expected: Cord inserted fully with no gap; AC outlet has power

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

Cuff fails to inflate when INFLATE switch pressed patient safety

Depressing INFLATE switch produces no cuff pressure increase; PRESSURE display does not change from 0

Ranked causes

1. Cuff not connected to CUFF connector (common)
2. Cuff hose kinked or blocked (occasional)
3. Low pressure alarm condition active (occasional)

First check

Verify cuff connector is fully inserted into CUFF port

Test point: CUFF connector
Expected: Cuff firmly seated with no visible gap

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

Cuff fails to deflate when DEFLATE switch pressed patient safety

Depressing DEFLATE switch produces no pressure decrease; PRESSURE display remains unchanged

Ranked causes

1. DEFLATE switch not held long enough (common)
2. Deflation valve malfunction or blockage (occasional)

First check

Hold DEFLATE switch continuously for 2 seconds

Test point: DEFLATE switch
Expected: Switch remains held for full 2-second duration

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

Cuff pressure below set point patient safety

Pressure display shows LO-P; pressure in cuff is 15 mmHg below set point

Ranked causes

1. Leak in system (common)
2. Hose occlusion (common)

First check

Visually inspect all tubing connections

Test point: cuff line connectors
Expected: No visible leaks or disconnections

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

Cuff pressure does not deflate to zero patient safety

TIME display shows CUFF NOT DEFL; pressure in deflated cuff is non-zero

Ranked causes

1. Kinks in hose restricting deflation (common)
2. Defective hose (occasional)

First check

Inspect hose for kinks

Test point: cuff line from valve to cuff
Expected: Straight, unobstructed tubing

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

Low pressure alarm activates with leak patient safety

PRESSURE display flashes 'LO-P' and audible alarm sounds when cuff pressure drops more than 15 mmHg below set point due to leak

Ranked causes

1. Cuff hose partially detached from unit connector (common)
2. Cuff puncture or valve leak (occasional)

First check

Verify cuff connector is fully seated in CUFF port

Test point: Cuff connector at CUFF port
Expected: Connector fully inserted with no visible gap or resistance to insertion

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

Unit fails power-up self-test

Unit does not complete initial self-check diagnostic; displays 'CAL FAIL' indicating out of calibration condition

Ranked causes

1. Pressure sensor out of calibration (common)
2. Internal circuit malfunction (occasional)

First check

Verify pressure display reads 0 mmHg at unit startup before any connections

Test point: PRESSURE display
Expected: 0 mmHg

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

Amplifier failure caution

TIME display shows FAIL; amplifier is out of range

Ranked causes

1. Amplifier circuit malfunction (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: Amplifier resets and alarm clears

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

Audible alarm sounds and cannot be silenced

Continuous alarm tone; ALARM SILENCE switch press does not stop sound; alarm message may continue on display

Ranked causes

1. Internal circuit malfunction detected (rare)

First check

Attempt ALARM SILENCE switch

Test point: ALARM SILENCE switch
Expected: Audible alarm stops for 30 seconds; display message continues

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

Battery failure

TIME display shows PLUG IN; battery voltage too low to ensure proper operation

Ranked causes

1. Battery depleted (common)

First check

Connect power and cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: Unit powers on and battery begins charging

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

Calibration out of specification caution

TIME display shows FAIL; transducer calibration is out of specification

Ranked causes

1. Pressure transducer requires recalibration (common)

First check

Perform unit calibration

Test point: pressure transducer
Expected: Calibration within specification after procedure

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

Cuff inflated on power up patient safety

Cuff pressurized to 50 mmHg or greater when unit is powered on

Ranked causes

1. Cuff pressure retained from previous procedure (common)

First check

Verify set pressure value

Test point: PRESSURE display
Expected: Set point appropriate for intended procedure

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

Cuff side leak detected patient safety

Leak alarm; leak present for at least 7 seconds

Ranked causes

1. Substantial leak in cuff or tubing (common)

First check

Inspect cuff and tubing for leak

Test point: cuff assembly and connections
Expected: No visible leaks or escaping pressure

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

Inflation time exceeds set limit patient safety

TIME display shows TIME UP; cuff has been inflated beyond set time limit

Ranked causes

1. Set time limit reached (common)

First check

Check elapsed time on display

Test point: TIME display
Expected: Time limit reached as set by operator

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

Line occlusion detected caution

PRESSURE display shows LINE OCCL; occlusion present in cuff tubing

Ranked causes

1. Hose kinks or crimping (common)

First check

Inspect entire cuff line

Test point: tubing from pump to cuff
Expected: Clear tubing without kinks or compressions

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

Low battery voltage

PRESSURE display shows BAT; TIME display shows BAT LOW; battery voltage is low but functional

Ranked causes

1. Battery needs charging (common)

First check

Verify unit is plugged in

Test point: AC power outlet
Expected: Unit connected to mains power

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

Math operation failure caution

TIME display shows FAIL; result of math operation was out of range

Ranked causes

1. Microprocessor math error (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: Math operation resets and alarm clears

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

Overpressure condition detected high voltage

PRESSURE display shows OVER; pressure switch detected pressure higher than unit range

Ranked causes

1. Pump runaway or pressure regulation failure (rare)

First check

Cycle ON/STANDBY switch immediately

Test point: ON/STANDBY switch
Expected: Pump stops and overpressure alarm clears

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

RAM memory check failure caution

TIME display shows FAIL; microprocessor failed RAM memory check

Ranked causes

1. RAM memory error (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: RAM check resets and alarm clears

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

ROM memory check failure caution

TIME display shows FAIL; microprocessor failed ROM memory check

Ranked causes

1. ROM memory corruption (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: ROM check resets and alarm clears

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

System failure detected caution

TIME display shows FAIL; internal diagnostics detected an error

Ranked causes

1. Internal hardware or software error (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: System diagnostics reset and alarm clears

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

Unit will not enter STANDBY mode caution

ON/STANDBY switch does not transition unit to STANDBY; unit remains powered on

Ranked causes

1. Cuff pressure at non-zero value (common)

First check

Verify cuff pressure reading on display

Test point: PRESSURE display
Expected: 0 mmHg

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

Valve failure caution

TIME display shows FAIL; improper valve combination occurred

Ranked causes

1. Valve circuit malfunction (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: Valve sequencing resets and alarm clears

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

Watchdog timer failure caution

TIME display shows FAIL; windowing watchdog system detected a malfunction

Ranked causes

1. Watchdog timeout or system hang (rare)

First check

Cycle ON/STANDBY switch

Test point: ON/STANDBY switch
Expected: Watchdog timer resets and alarm clears

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

Error codes

Code	Meaning	Trigger	Severity
`AMP`	Amplifier is out of range	Internal diagnostics detect amplifier malfunction	error
`BAT LOW`	Battery voltage is low but functional	Battery voltage drops below normal operating threshold but above critical	warning
`CAL`	Pressure transducer calibration is out of specification	Calibration check during power-up or diagnostic	error
`CUFF NOT DEFL`	Pressure in deflated cuff is non-zero	After deflation command, pressure remains above zero	error
`HI-P`	Cuff pressure is 15 mmHg above set point	Pressure sensor detects high cuff pressure	warning
`INFL`	Cuff was pressurized on power up at 50 mmHg or greater	High cuff pressure detected at power-up	warning
`LEAK`	A substantial leak has been present for at least 7 seconds	Continuous pressure drop detected over 7-second period	error
`LINE OCCL`	Occlusion detected in cuff tubing	Pressure cannot reach set point during inflation	error
`LO-P`	Cuff pressure is 15 mmHg below set point	Pressure sensor detects low cuff pressure	warning
`MATH`	Result of math operation was out of range	Microprocessor arithmetic overflow or underflow	error
`OVER`	Pressure exceeds unit operating range	Pressure switch detects overpressure condition	critical
`PLUG IN`	Battery voltage is too low to ensure proper operation	Battery voltage drops to critical level	error
`RAM`	Microprocessor failed RAM memory check	RAM checksum or parity error detected	critical
`ROM`	Microprocessor failed ROM memory check	ROM checksum or parity error detected	critical
`SYS`	Internal diagnostics detected a system error	Self-test or runtime diagnostic detects internal fault	error
`TIME UP`	Cuff inflation time has exceeded set time limit	Elapsed inflation time reaches set time limit	warning
`VALV`	Improper valve combination occurred	Valve sequencing error during operation	error
`WDT`	Windowing watchdog system detected a malfunction	Watchdog timer timeout or system hang	error

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.