Bendix EC-60 UDS 143 / SPN 1808 FMI 13 — YRS Sign Check Not Finished

Code Details

Plain-English Meaning

The EC-60 cannot confirm a valid calibration reference for the yaw rate sensor (YRS). Calibration establishes the sensor's zero-rate baseline while the vehicle is stationary on level ground; without this reference the EC-60 cannot trust the YRS data for ESP yaw-correction. A sign-check fault means the EC-60 could not verify that the sensor's output direction matches the expected installation orientation — the zero rate may be set but polarity is unconfirmed.

The Bendix EC-60 table maps UDS code 143, blink code 22-15, J1587 089-13, and J1939 SPN 1808 FMI 13 to this ABS/ATC/ESP diagnostic entry. The Bendix source indicates an ABS and/or ATC/ESP warning lamp can be on for this entry. The EC-60 continuously monitors wheel speed sensor circuits, pressure modulation valve output drivers, supply voltage quality, J1939 network data from the engine and transmission controllers, and internal self-diagnostic routines. When any monitored value falls outside its acceptable range — or a circuit does not respond as the module expects — the EC-60 logs a diagnostic trouble code and may disable the affected ABS, ATC, or ESP function. Bendix ACOM Pro or a compatible diagnostic interface is the required tool for reading live sensor data, running actuator tests, performing calibrations, clearing latched codes, and adjusting EC-60 configuration parameters. Generic J1939 scan tools can read the SPN/FMI but cannot access EC-60-specific live data screens or configuration settings.

Common Symptoms

• ESP/stability lamp on
• ESP yaw-correction suspended until a valid calibration is confirmed
• ABS and ATC continue to operate normally
• Code commonly appears after YRS replacement, chassis repair, or post-service ACOM session
• Sensor may produce an electrical output that reads normal — the fault is a missing reference, not a dead sensor

Possible Causes

Possible causes may include the items below. The list is not a parts diagnosis.

• YRS installed in the correct location but facing the wrong direction — sign-check verifies output polarity after the zero reference is set
• Vehicle was in motion, on a slope, or subject to wind during the calibration attempt
• ACOM calibration session was disconnected or timed out before the procedure completed
• YRS power or CAN communication fault preventing the sensor from completing its internal initialization
• Replacement YRS with a different part number that requires a fresh calibration cycle

First Checks

• Position the vehicle on a level, stable surface with the engine off or at low idle — no traffic passing, no wind rocking the cab.
• Connect Bendix ACOM and navigate to the YRS calibration function for this EC-60 application.
• Follow the ACOM procedure exactly; confirm the vehicle is completely stationary when prompted to capture the zero-rate reference.
• If sign-check fails despite correct calibration, verify the sensor mounting direction matches the Bendix installation diagram — arrow markings on the sensor indicate the required forward-facing direction.
• After successful calibration, clear stored codes and confirm ESP resumes normal operation on a short test drive.

Can I Keep Driving?

A stability sensor fault (yaw rate, steering angle, or lateral acceleration) disables ESP stability intervention while leaving ABS and ATC intact. The vehicle handles as it would without electronic stability control. Drive with that in mind — cornering, evasive maneuvers, and braking on slippery surfaces carry a higher risk. Stability sensor faults should be addressed before returning the vehicle to regular line-haul or severe-weather service.

Related Lookup Pages

• FMI 13 explanation
• Bendix manufacturer hub
• ABS / ATC / ESP fault codes
• ABS Light symptom page
• Brake Warning Light symptom page
• Search this code