Treadmills · T650 family

SportsArt T650: troubleshooting and error codes

The ServiceForge knowledge base holds 38 documented symptoms for the SportsArt T650, with 92 ranked causes, 95 diagnostic checks with test points and expected values, and 20 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

HTR handlebar not detected during operation

LED indicators do not light or flash as expected; heart rate not displayed

Ranked causes

1. LED2 does not light (common)
2. LED3 does not light (common)
3. LED4 does not light (occasional)
4. LED1 does not light (occasional)
5. No heart rate on display (occasional)

First check

Observe LED2 indicator when holding HTR handlebar

Test point: LED2
Expected: Lights

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

Display reacts to key press without actual key input

When unit is turned on without pressing any keys, display shows reaction as if keys were pressed

Ranked causes

1. Soft key electrical contact issue or bridge board malfunction (occasional)
2. 9-pin cable short or signal line interference (occasional)
3. Bridge board power distribution or signal processing malfunction (occasional)
4. Display board CPU software or firmware issue (rare)

First check

Visually inspect soft key contacts for debris or corrosion

Test point: Soft key connectors and switch contacts
Expected: Clean, dry, undamaged soft key contacts

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

Display shows no reaction to key press

When unit is turned on and a key is pressed, the display does not respond to the key input

Ranked causes

1. Display board CPU malfunction (occasional)
2. 9-pin cable signal transmission failure (occasional)
3. Bridge board signal processing failure (occasional)
4. Soft key contact or electrical failure (occasional)

First check

Test display board basic functions

Test point: Display CPU outputs and signal generation
Expected: Display board generates control signals when keys are pressed

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

Fan does not operate when FAN key pressed

Display shows fan setting (LOW/MID/HIGH) but fan motor does not run

Ranked causes

1. Fan motor defective (unknown)
2. Fan cable disconnected or damaged (unknown)
3. Fan board output circuit defective (unknown)
4. Display board not communicating fan speed to fan board (unknown)

First check

Press <FAN> key and observe display

Test point: Display output
Expected: Display shows FAN Low (Mid/High) or cycles through STOP, LOW, MID, HIGH

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

HTR board LED indicators not responding

One or more LED indicators not lighting or flashing as expected during test procedure

Ranked causes

1. POLAR receiver not detecting signal (common)
2. HTR handlebar not being held or contact not detected (common)
3. HTR signal not arriving from handlebars (occasional)
4. HR board output not emitting signal to display (rare)

First check

Do not hold HTR handlebar

Expected: HTR board indicators do not light

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

Incline motor does not operate caution

Incline key pressed, display values change but motor does not move up or down

Ranked causes

1. Display board does not send incline up/down signal (occasional)
2. Incline wire open circuit or short (occasional)
3. Drive board components damaged (occasional)
4. Incline motor open circuit (occasional)

First check

Measure incline motor resistance for open circuit

Test point: Motor terminals
Expected: Continuity present or measurable resistance
Tools: DMM

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

Motor encoder error E-1-1

Unit does not operate; E-1-1 error displayed on control panel

Ranked causes

1. Drive board not detecting encoder signal (common)
2. Encoder cable disconnection (common)
3. Servo motor encoder failure (occasional)
4. Drive board failure (occasional)

First check

Turn unit off and on

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

Motor excessive heat (E-1-2) caution

Display shows E-1-2 error; unit operates at reduced speed (half speed). Thermal sensor detects motor temperature; excessive heat signals abnormal operation.

Ranked causes

1. Drive board not receiving thermal sensor signal (common)
2. Motor drawing excessive current (occasional)
3. Worn or over-tight walk belt (occasional)
4. Insufficient cool-down time (occasional)

First check

Verify thermal sensor wire connection

4 more checks with pass and fail actions are in ServiceForge. Connect ServiceForge to your AI

Unit does not start up

Display does not beep or light up when powered on

Ranked causes

1. No power to drive board (common)
2. Component electrical short on drive board (common)
3. Display not receiving VBB voltage (occasional)
4. Display IC failure (occasional)

First check

Power cord connected

7 more checks with pass and fail actions, 8 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Walk belt misaligned or off-center

Walk belt is crooked or positioned too far to one side, with uneven gap between belt and frame

Ranked causes

1. Rear roller adjustment screws out of specification (common)
2. Front roller positioning incorrect (common)
3. Walk belt left/right adjustment screws misaligned (common)
4. Top screw gap adjustment needed (occasional)

First check

Inspect gap size between belt and frame at top and bottom

Test point: Top and bottom belt edges
Expected: Gap size equal top to bottom

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

Calibration: Walk belt tracking and tension caution

Belt tracks to one side or belt is loose or tight during operation at 4 KPH/2.5 MPH

Ranked causes

1. Belt tracks to one side (common)
2. Belt is loose (common)
3. Belt is too tight (occasional)

First check

Set treadmill speed and observe belt centering

Test point: Treadmill speed control
Expected: 4 KPH / 2.5 MPH

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

FAN key does not toggle fan setting

Pressing <FAN> key does not cycle through STOP→LOW→MID→HIGH→STOP or display does not show fan mode

Ranked causes

1. FAN key defective or stuck (unknown)
2. Display board not responding to FAN key input (unknown)
3. Fan cable or connector loose (unknown)

First check

Press <FAN> key and listen for audible click

Test point: FAN key on control panel
Expected: Audible click with each press; no stuck or stiff feeling

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

Fuse blows immediately on power-up caution

Main fuse burns out when power switched on; replacing fuse results in immediate reburn

Ranked causes

1. Motor current excessive (common)
2. Wire connections not properly attached (common)
3. Drive board component malfunction causing electrical short (occasional)

First check

EMI filter wire connections

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

Heart rate signal not detected when holding handlebar

When user holds HTR handlebar contacts, display shows no heart rate value or response

Ranked causes

1. HTR handlebar contacts or cables defective (common)
2. HTR board does not detect handlebar signal (occasional)
3. Display does not detect HTR signal (occasional)

First check

Verify handlebar contacts are clean and making contact

Test point: HTR contact left and right
Expected: Contacts clean and free of corrosion
Tools: Visual inspection

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

Incline calibration error caution

Display shows E-3-1 error, indicating incline calibration failed; incline motor does not reach 0% home position or calibration switch not detected

Ranked causes

1. Calibration switch wire disconnected from drive board (common)
2. Calibration switch malfunction (occasional)
3. Drive board failure (rare)

First check

Drive board detects calibration switch signal and transmits to display board

Test point: Drive board connection to calibration switch
Expected: Signal received at drive board
Tools: Visual inspection, multimeter

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

Motor does not operate caution

Walk belt does not rotate when SPEED key pressed

Ranked causes

1. Drive board does not emit voltage to motor (common)
2. Motor malfunction (occasional)
3. Encoder cable not properly inserted or defective (occasional)

First check

Verify display board sends speed signal

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

No heart rate reading during telemetry test

Display does not show heart rate reading during static or active test with telemetry strap in place

Ranked causes

1. Telemetry heart rate receiver not reading signals in optimal conditions (common)
2. Motor interference affecting reception during active test (occasional)
3. Defective telemetry strap or receiver (rare)

First check

Perform static test without motor running

Test point: Display reading
Expected: Heart rate reading displayed

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

No telemetry heart rate signal

Telemetry receiver does not display heart rate from transmitter; no signal detected on display board.

Ranked causes

1. Telemetry strap defective or batteries low (common)
2. Telemetry receiver defective or not detecting signal (occasional)
3. Three-pin cable not connected (common)

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

Unit stops during operation with communication error

Error message E-8-2 appears during operation; unit stops operating. Communication between display and drive board fails.

Ranked causes

1. Display IC not inserted properly (occasional)
2. Data cable connection fault (common)
3. Drive board failure (occasional)

First check

Verify display IC is properly inserted

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

Calibration verification failed

After calibration steps, incline display does not show 0% when idle or fails to reach 15% when incline key is pressed

Ranked causes

1. Calibration switch not engaged properly (occasional)
2. LED indicators on drive board not functioning (rare)

First check

Verify incline moves fully to lowest position during downward calibration

Test point: Incline mechanical position and calibration switch
Expected: Motor stops when switch is fully engaged at 0% position

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

Calibration: AC Motor Incline

Incline motor must be calibrated to establish 0% position and 15% maximum position limits via software procedure

Ranked causes

1. Incline requires initial calibration or recalibration after replacement/maintenance (common)
2. Incline requires calibration when unit is not in normal operation mode (occasional)

First check

Press INCL▲ key continuously and observe incline display and LED3 on drive board

Test point: Incline display window, LED3 on drive board
Expected: Display shows 15%, LED3 lights when motor operates and extinguishes when motor stops

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

Display board power supply not responding high voltage

No power reading on voltmeter when unit power is turned on; Power switch LED does not light

Ranked causes

1. Cable connections disconnected or loose (common)
2. Drive board failure (occasional)

First check

Measure VCC voltage

Test point: VCC test point
Expected: +5V
Tools: DC voltmeter

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

E-2-1 IGBT excessive current error caution

Display shows E-2-1 error indicating IGBT over current detection by the drive board

Ranked causes

1. IGBT over current signal detected (common)
2. Servo motor winding break (occasional)

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

Incline motor does not respond to control input high voltage

Unit does not move up or down when INCL<▲> or INCL<▼> key is pressed; no AC voltage at CON5 connector

Ranked causes

1. Fuse F13A not connected properly or burnt (common)
2. Drive board failure (occasional)

First check

Verify AC voltage output at CON5 connector

Test point: CON5 white and black wires (incline up) or white and red wires (incline down)
Expected: 110 VAC (USA areas) or 220/240 VAC (Europe areas)
Tools: Voltmeter set to 600 VAC range

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

E-1-1 error display

Display shows E-1-1 indicating motor encoder malfunction

Ranked causes

1. Signal detection failure at drive board (common)

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

E-2-2 IGBT Excessive Heat Error caution

Display shows E-2-2, unit operates at half speed. Drive board detects IGBT over heat signal and transmits to display board.

Ranked causes

1. IGBT over heat signal detected by drive board (common)

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

E-4-2 low voltage error caution

Display shows E-4-2 low voltage error message indicating abnormal power supply voltage below normal level

Ranked causes

1. Abnormal power supply voltage (common)

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

E-4-3 high voltage error caution

Display shows E-4-3 high voltage error message indicating abnormal power supply voltage above normal level

Ranked causes

1. Abnormal power supply voltage (common)

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

E-8-1 error at startup, unit does not operate

Display shows E-8-1 error message when power is turned on. Unit does not operate.

Ranked causes

1. No communication between display board and drive board (common)

First check

Verify display IC is fully inserted in its socket

Test point: Display board IC socket
Expected: IC fully seated

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

Fan board voltage out of range

Voltmeter reading does not match expected VDC for fan speed setting (STOP/LOW/MID/HIGH)

Ranked causes

1. Fan board defective or voltage regulator failure (unknown)

First check

Measure voltage on CON1 terminal pins with voltmeter set to VDC

Test point: CON1 brown and black terminals
Expected: 0V at STOP, 6V at LOW, 9V at MID, 12V at HIGH, Exact match required
Tools: Voltmeter (VDC setting)

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

HTR handlebar continuity test failed

Resistance or continuity measurements between HTR board connector pins do not match expected values

Ranked causes

1. HTR board connector loose or corroded (common)

First check

Measure continuity between A-a

Test point: A-a
Expected: Continuity

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

Incline calibration sensor malfunction

Incline calibration sensor does not respond or shows incorrect resistance reading

Ranked causes

1. Incline calibration sensor defective (common)

First check

Measure incline calibration sensor resistance with voltmeter

Test point: Incline calibration sensor terminals
Expected: 0Ω, ±0 Ω (exact)
Tools: Voltmeter set to 20K Ω range

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

Incline does not move or moves slowly

Incline motor fails to respond to commands or moves at incorrect speed during up or down travel

Ranked causes

1. Incorrect cable connections to incline motor (common)

First check

Measure voltage at incline motor UP terminal

Test point: Black - White connectors
Expected: 110v or 220v depending on unit configuration V, nominal supply voltage
Tools: Multimeter

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

Incline reaches wrong position or stalls

Incline motor stalls or does not reach commanded position (0-15% range)

Ranked causes

1. Loss of voltage to incline motor during travel (occasional)

First check

Verify DRV LED illumination during UP command

Test point: LED 3 indicator
Expected: LED 3 ON continuously during UP travel
Tools: Visual inspection

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

Motor thermal sensor not responding

Thermal sensor shows electrical open (OL) when measured, but motor is not overheated to the touch

Ranked causes

1. Thermal sensor malfunction (common)

First check

Measure thermal sensor resistance

Test point: CON1 thermal sensor switch wire terminals
Expected: 0, continuity Ω
Tools: Ohmmeter set to 200Ω

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

Motor windings open

Electrical open circuit detected in motor windings during resistance testing

Ranked causes

1. Motor winding broken or open (unknown)

First check

Measure resistance between motor winding phases

Test point: Red-White
Expected: 0.1Ω, continuity expected
Tools: Ohmmeter set to 200Ω range

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

Motor windings shorted

Electrical short detected between motor winding phases or to ground during resistance testing

Ranked causes

1. Motor windings shorted or broken (unknown)

First check

Measure resistance between motor winding phases

Test point: Green-Red
Expected: OL
Tools: Ohmmeter set to 200Ω range

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

Telemetry heart rate signal incorrect

Displayed heart rate value from telemetry receiver does not match actual patient heart rate or is erratic.

Ranked causes

1. Display or CPU defective (rare)

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

Error codes

Code	Meaning	Trigger	Severity
`E-1-1`	Motor encoder error - drive board not detecting encoder signal	Encoder signal not reaching drive board; signal loss during motor operation	error
`E-1-2`	Motor excessive heat error	Thermal sensor detects motor overheating or drive board fails to receive sensor signal	unknown
`E-1-3`	Motor speed error detected by display board	Drive board does not receive encoder signal from motor	error
`E-2-1`	IGBT excessive current error	IGBT over current signal detection	error
`E-2-2`	IGBT Excessive Heat Error	Drive board detects IGBT over heat signal	error
`E-4-2`	Low voltage error	Abnormal power supply below nominal	unknown
`E-4-3`	High voltage error	Abnormal power supply above nominal	unknown
`E-8-1`	Communication error at start	No communication detected between display board and drive board during power-on startup	error
`E-8-2`	Communication Error During Operation	Display CPU detects abnormal communication between display and drive board during operation	error
`ERROR_1_1_`	Servo motor encoder malfunction	Servo motor encoder position feedback failure	error
`ERROR_1_2_`	Servo motor has overheated	Servo motor temperature exceeds safe operating threshold	warning
`ERROR_1_3_`	Servo motor sped up without command	Uncontrolled servo motor acceleration detected	error
`ERROR_2_1_`	IGBT excessive current	IGBT power transistor overcurrent condition detected	error
`ERROR_2_2_`	IGBT excessive heat	IGBT power transistor temperature exceeds threshold	warning
`ERROR_3_1_`	Incline motor recalibration error	Incline motor position calibration failure	error
`ERROR_4_1_`	Power switch is off	Main power switch is in off position during operation	warning
`ERROR_4_2_`	Power supply voltage is too low	Supply voltage below minimum operating threshold	warning
`ERROR_4_3_`	Power supply voltage is too high	Supply voltage exceeds maximum operating threshold	warning
`ERROR_8_1_`	Signal error upon startup	Signal integrity error detected during system startup	error
`ERROR_8_2_`	Signal error after startup	Signal integrity error detected after system started	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.