Decoding fault codes EBS 2 WABCO MAN / Full list
- SPN 03101
- SPN 03107
- SPN 03109
- SPN 03120
- SPN 03121
- SPN 03121
- SPN 03123
- SPN 03131
- SPN 03132
- SPN 03134
- SPN 03136
- SPN 03138
- SPN 03139
- SPN 03149
- SPN 03151
- SPN 03157
- SPN 03159
- SPN 03171
- SPN 03182
- SPN 03184
- SPN 03186
- SPN 03201
- SPN 03207
- SPN 03209
- SPN 03220
- SPN 03221
- SPN 03222
- SPN 03223
- SPN 03231
- SPN 03236
- SPN 03241
- SPN 03244
- SPN 03249
- SPN 03251
EBS 2 Wabco MAN — Electronic Brake System Error Codes and Error Interpretations
The Wabco Electronic Brake System EBS 2 is used in MAN trucks and is responsible for the correct operation of the brakes, ABS, ASR, and other active safety systems. When malfunctions occur, the EBS control unit records errors that are displayed as SPN and FMI diagnostic codes.
This page provides a decryption of Wabco MAN EBS 2 fault codes, as well as a description of the causes of the errors and diagnostic recommendations.
How to read EBS fault codes (SPN / FMI)
EBS diagnostic errors are displayed in the following format:
SPN XXX FMI X
- SPN (Suspect Parameter Number) — identifies a specific node, sensor, or system parameter.
- FMI (Failure Mode Identifier) — identifies the type of fault (open, short, invalid signal, etc.)
FMI examples:
- FMI 3 — Signal not recognized
- FMI 4 — Open circuit
- FMI 5 — Short circuit to ground
- FMI 6 — Short circuit to power
- FMI 10 — CAN bus communication error
Understanding the SPN/FMI format allows you to quickly determine the direction of troubleshooting.
Main causes of Wabco MAN EBS 2 errors
In practice, most EBS 2 Wabco errors occur for the following reasons:
- damaged or oxidized wiring and connectors
- malfunctioning pressure sensors or brake switches
- power supply problems (terminal 30, ground)
- errors or breaks in the J1939 CAN bus
- software failures in the EBS control unit
- failure of the Wabco EBS unit itself
Timely decoding of the diagnostic code allows to avoid serious brake system failures and costly repairs.
What do the STOP and ABS indicators mean?
If a malfunction occurs with the Wabco EBS 2, various signals may be displayed on the MAN instrument cluster:
- STOP yellow — a malfunction is present, but basic braking functions are retained
- STOP red — critical error, EBS functions are limited or disabled
- ABS / ASR — disabling the auxiliary stabilization systems and traction control systems
If the red STOP indicator appears, operation of the vehicle is not recommended until the cause of the malfunction is completely rectified.
How to properly diagnose the Wabco EBS 2
Recommended procedure for diagnosing the electronic braking system:
Read the fault code with a MAN diagnostic scanner / Find the corresponding code SPN / FMI in the list below / Check:
- Wiring condition
- EBS unit connectors
- Power and ground
- Sensor resistance
If necessary:
- Update the unit software
- Replace the faulty sensor or module
- Replace the EBS control unit
Important: Replacing the EBS unit without a complete diagnostic often does not solve the problem if the cause is in the wiring or power supply.
Why is it important to use EBS code decoding?
Using accurate Wabco EBS 2 error decoding allows you to:
- reduce troubleshooting time
- avoid Unnecessary replacement of expensive components.
- Accurately identify the faulty component.
- Improve the operating safety of MAN vehicles.
- Reduce commercial vehicle downtime.
Wabco MAN EBS 2 Error Codes.
Below is a complete list of Wabco MAN EBS 2 Error Codes, including:
- Brake sensor errors.
- EBS power supply faults.
- J1939 CAN bus faults.
- Control unit faults. Wabco
- Other Electronic Brake System Diagnostic Codes
Each code contains:
- Description of the malfunction
- Possible causes
- Inspection and repair recommendations
Rotation sensor, front axle, left side.
The STOP indicator light is yellow. The following are disabled: Front left axle ABS, ESP, and ASR.
No signal from the sensor.
Check the sensor (B119) for opens and shorts.
Check the resistance of the sensor (B119) (950 - 1930 Ohm).
Check the wiring and contacts in the connectors between the EBS unit (A402) (X2/2 and X2/3) and the sensor (B119).
If no fault is detected, replace the EBS unit (A402).
Toothed wheel, front axle, left side.
The STOP indicator light is yellow. FMI 0: ESP is deactivated. FMI 9: Disabled: Front axle ABS left, ESP, ASR.
The signal from the left front axle sensor is not identified.
Check the toothed wheel for damage and contamination.
Check the condition of the wheel bearing.
Wheel brake, toothed wheel, speed sensor, front axle, left side.
The STOP warning lamp lights up yellow. FMI 0: Disabled ESP. FMI 9: Disabled: Front axle ABS left, ESP, ASR.
The signal from the left front axle sensor is not identified.
Check the toothed wheel for damage and contamination.
Check the condition of the wheel bearing.
Brake pad wear sensor, power supply, front axle, left side or front axle.
The STOP indicator light is yellow. User functions are unlimited.
Front axle brake pad wear sensor power failure (B332/B333).
Check the wiring and contacts in the pad wear sensor connectors (Pin X1/8+, Pin X1/16-).
Check the pad wear sensors for internal short circuits.
If the sensors and wiring are normal, replace the EBS unit (A402).
Pad wear sensor A, Signal, front axle, left side.
The STOP indicator light is yellow. User functions are not limited.
The signal from the sensor is outside the acceptable range.
Check the wiring and contacts in the wear sensor connectors (B333).
Check the pad wear sensor for internal shorts.
If the sensor and wiring are normal, replace the EBS unit (A402).
ABS exhaust valve, feedback information, front axle, left side.
STOP warning light illuminates yellow. FMI 5, 10: Disabled: ABS, front axle left, ESP. FMI 6: Disabled: Front axle ABS, ESP.
ABS valve cannot be adjusted.
Check the wiring and contacts in the ABS valve (Y125) connectors for opens and shorts. Check the ABS valve (Y125) for internal shorts and proper operation.
If no fault is detected, replace the EBS unit (A402).
ABS outlet valve, return information, front axle, left side.
The STOP warning light is yellow. FMI 5, 10: The following are deactivated: ABS front axle left, ESP. FMI 6: Disabled: Front axle ABS, ESP.
ABS valve cannot be adjusted.
Check the wiring and contacts in the ABS valve (Y125) connectors for opens and shorts, check the ABS valve (Y125) for internal shorts and proper operation.
If no fault is detected, replace the EBS unit (A402).
ABS outlet and inlet valves, feedback information, front axle, left side.
FMI 10: The STOP warning light is yellow. The following are disabled: front axle ABS, left, ESP. The ABS valve is not adjusted.
FMI 7: The STOP warning light is red. The following are disabled: front axle ABS, ESP. The ABS valve has an external, independent actuation.
Check the wiring and contacts in the ABS valve (Y125) connectors for opens and shorts, check the ABS valve (Y125) for internal shorts and proper operation.
If no fault is found, replace the EBS unit (A402).
Proportional control valve, front axle, left side or front axle.
The STOP indicator light is yellow. The following functions are disabled: front axle brake pressure control, front axle ABS, and ESP.
The proportional control valve in the EBS unit (A402) is faulty.
Replace the EBS unit (A402).
ABS valves, front axle.
FMI 5: The STOP indicator lamp is yellow. User functions are not limited. Check the wiring and contacts in the front axle ABS valve connectors (Y125 left, Y126 right), check the front axle ABS valves for internal short circuits and correct operation. If no fault is found, replace the EBS unit (A402).
FMI 6: The STOP indicator lamp is yellow. The front axle ABS and ESP are deactivated. Check the wiring and contacts in the front axle ABS valve connectors (Y125 left, Y126 right). Check the front axle ABS valves for internal short circuits and proper operation. If no fault is detected, replace the EBS unit (A402).
FMI 3: The STOP indicator lamp glows red. The following functions are disabled: front, rear, tag axle brake pressure regulation, trailer brake control valve, ABS, ESP, and ASR. Check the parameters in the EBS unit (A402).
Pneumatic overpressure circuit.
The STOP indicator light is yellow. User functions are not limited.
Pneumatic backup failure.
Check the pneumatic brake pressure line to the front axle for kinks and blockages.
Check the pneumatic brake line to the front axle for breaks and air leaks from the connections.
Check the backup lines to the rear axle and the trailer brake control valve for air leaks.
Take a PC test of the backup pressure in the front axle circuit.
If no fault is detected, replace the EBS unit (A402).
Rotation sensor, front axle, right side.
The STOP warning light is yellow. The following are disabled: ABS, front right axle, ESP, and ASR.
No signal from the sensor.
Check the sensor (B120) for opens and shorts.
Check the resistance of the sensor (B120) (950 - 1930 ohms).
Check the wiring and contacts in the connectors between the EBS unit (A402) and the sensor (B120).
If no fault is detected, replace the EBS unit (A402).
Toothed wheel, front axle, right side.
The STOP indicator light is yellow. FMI 0: ESP is deactivated. FMI 9: Disabled: Front axle ABS right, ESP, ASR.
The signal from the right front axle sensor is not identified.
Check the toothed wheel for damage and contamination.
Check the condition of the wheel bearing.
Wheel brake, toothed wheel, speed sensor, front axle, right side.
The STOP indicator light is yellow. The following are disabled: right front axle ABS, ESP, and ASR.
The signal from the right front axle sensor is not identified.
FMI 1: Check the wheel brake for abnormal vibrations, check the sensor mountings, and check the sensor wiring insulation. If no fault is detected, replace the EBS unit (A402).
FMI 2: Check the distance between the toothed wheel and the sensor, and check the sensor output voltage for very low voltage. If no fault is detected, replace the EBS unit (A402).
FMI 8: Check the sensor and its mounting for vibrations and oscillations; check the wheel brake for abnormal vibrations while driving.
Brake pad wear sensor A, signal, front axle, right side.
The STOP indicator lamp lights up yellow. User functions are unlimited.
The signal from the sensor is outside the acceptable range.
Check the wiring and contacts in the wear sensor connectors (B332).
Check the pad wear sensor for internal short circuits.
If the sensor and wiring are normal, replace the EBS unit (A402).
ABS inlet valve, feedback information, front axle, right side.
The STOP indicator light is yellow. FMI 5, 10: Disabled: ABS front axle right, ESP. FMI 6: Disabled: Front axle ABS, ESP.
ABS valve cannot be adjusted.
Check the wiring and contacts in the ABS valve (Y126) connectors for opens and shorts. Check the ABS valve (Y126) for internal shorts and proper operation.
If no fault is detected, replace the EBS unit (A402).
ABS outlet valve, return information, front axle, right side.
The STOP warning light is yellow. FMI 5, 10: Disabled: Front right ABS, ESP. FMI 6: Disabled: Front right ABS, ESP.
The ABS valve cannot be adjusted.
Check the wiring and contacts in the ABS valve (Y126) connectors for open circuits and short circuits. Check the ABS valve (Y126) for internal short circuits and proper operation.
If no fault is detected, replace the EBS unit (A402).
ABS outlet and inlet valves, feedback information, front axle, right side.
FMI 10: The STOP warning lamp lights up yellow. The following are deactivated: front axle ABS, right, ESP. The ABS valve is not adjusted.
FMI 7: The STOP warning lamp lights up red. The following are deactivated: front axle ABS, ESP. The ABS valve has an external, independent actuation.
Check the wiring and contacts in the ABS valve (Y126) connectors for opens and shorts, check the ABS valve (Y126) for internal shorts and proper operation.
If no fault is found, replace the EBS unit (A402).
Rotation sensor, rear axle, left side.
The STOP indicator light is yellow. The following are disabled: ABS on the left rear axle, ESP, and ASR.
There is no signal from the sensor.
Check the sensor (B121) for opens and shorts.
Check the resistance of the sensor (B121) (950 - 1930 ohms).
Check the wiring and contacts in the connectors between the pressure control module (Y264) and the sensor (B121).
If no fault is detected, replace the EBS unit (A402).
Toothed wheel, rear axle, left side.
The STOP indicator light is yellow. FMI 0: ESP is deactivated. FMI 9: Left rear axle ABS, ESP, and ASR are disabled.
The signal from the left rear axle sensor is not identified.
Check the toothed wheel for damage and contamination.
Check the condition of the wheel bearing.
Wheel brake, toothed wheel, speed sensor, rear axle, left side.
The STOP indicator light is yellow. The following are disabled: left rear axle ABS, ESP, and ASR.
The signal from the left rear axle sensor is not identified.
FMI 1: Check the wheel brake for abnormal vibrations, check the sensor mountings, and check the sensor wiring insulation. If no fault is detected, replace the EBS unit (A402).
FMI 2: Check the distance between the toothed wheel and the sensor, and check the sensor output voltage for very low voltage. If no fault is detected, replace the EBS unit (A402).
FMI 8: Check the sensor and its mounting for vibrations and oscillations; check the wheel brake for abnormal vibrations while driving.
Brake pad wear sensor, power supply, rear axle, left side or rear axle.
The STOP indicator light is yellow. User functions are unlimited.
Power failure for rear axle brake pad wear sensors (B335 left / B334 right).
Check the wiring and contacts in the pad wear sensor connectors.
Check the pad wear sensors for internal short circuits.
If the sensors and wiring are normal, replace the rear axle pressure control module (Y264).
Pad wear sensor A, signal, rear axle, left side.
The STOP indicator light is yellow. User functions are not limited.
The signal from the sensor is outside the acceptable range.
Check the wiring and contacts in the wear sensor connectors (B335).
Check the brake pad wear sensor for internal shorts.
If the sensor and wiring are normal, replace the rear axle pressure control module (Y264).
Brake pad wear sensor B, signal, tag axle, left side.
The STOP indicator light is yellow. User functions are not limited.
The signal from the sensor is outside the permissible range.
Check the wiring and contacts in the wear sensor connectors (B389).
Check the pad wear sensor for internal short circuits.
If the sensor and wiring are normal, replace the rear axle pressure control module (Y264).
Pressure sensor, power supply, rear axle, left side or rear axle.
FMI 1, 9: STOP indicator lamp Lights up yellow.
FMI 1: Rear axle ABS and ESP are disabled.
FMI 9: No information from the pressure sensor for the EBS unit pressure setting mode (A402); ESP, ABS, and ASR are disabled. The signal from the pressure sensor is outside the permissible range.
FMI 1, 9: Check the pneumatic lines of the rear axle pressure control module for residual pressure. If no fault is found, replace the rear axle pressure control module (Y264).
FMI 2: The STOP indicator lamp lights up red. The following functions are disabled: rear axle brake pressure control, ABS, ESP, and ASR. Check the compressed air supply to the rear axle pressure control module (Y264), check the reserve pressure pneumatic lines to the rear axle pressure control module (Y264) for pinches and blockages, check the brake air lines to the rear axle pressure control module (Y264) for breaks and air leaks at the connections, measure and evaluate the plausibility of the reserve pressure readings in the rear axle circuit using a PC. If no fault is detected, replace the rear axle pressure control module (Y264).
Redundant valve, rear axle left side or rear axle.
FMI 5, 6, 10: STOP warning lamp lights up yellow. Disabled: front axle ABS, ESP. Rear axle ABS function is limited. Failure of the rear axle redundant brake system valve. Check parameters in the EBS control unit (A402), check wiring and connector contacts of the rear axle redundant valve (Y368) for open circuits and short circuits, check the rear axle redundant valve (Y368) for correct operation and plausibility of the output signal. If no fault is found, replace the EBS control unit (A402).
FMI 3: STOP warning lamp lights up red. Disabled: brake pressure regulation of front, rear and auxiliary axles, ABS, ESP, ASR. Failure of the rear axle redundant brake system valve. Check parameters in the ABS control unit (A402).
Exhaust and inlet valve, feedback, rear axle, left side or rear axle.
STOP warning lamp lights up red. Disabled: rear axle brake pressure regulation and trailer control valve, ABS, ESP, ASR.
Failure of the brake pressure valve in the rear axle pressure modulation module (Y264).
Replace the rear axle pressure modulation module (Y264).
Software mismatch between the EBS control unit (A402) and the pressure modulation module, rear axle, left side or rear axle.
STOP warning lamp lights up red. Disabled: brake pressure regulation of front, rear and auxiliary axles, ABS, ESP, ASR.
Incorrect parameters or system configuration.
Check the rear axle pressure modulation module (Y264) installed on the chassis for correct part number according to the chassis specification.
Check parameters in the EBS control unit (A402).
Pressure modulation module, rear axle left side or rear axle, arithmetic test failed.
STOP warning lamp lights up red. Disabled: rear and auxiliary axle brake pressure regulation, trailer control valve, ABS, ESP, ASR.
Electronic failure in the pressure modulation module.
Replace the rear axle pressure modulation module (Y264).
Redundant pressure system, rear axle.
STOP warning lamp lights up yellow. User functions are not restricted.
Pneumatic redundancy failure.
Check air supply to the pressure modulation module (Y264) for low pressure, check pneumatic redundant pressure lines of the rear axle pressure modulation module (Y264) for blockages and kinks, check pneumatic lines to the pressure modulation module (Y264) for breaks and air leaks at connections.
Check the rear axle redundant valve (Y368) for correct operation.
Measure and evaluate the plausibility of the rear axle redundant pressure readings using a PC.
If no fault is found, replace the rear axle pressure modulation module (Y264).
Wheel speed sensor, rear axle, right side.
STOP warning lamp lights up yellow. Disabled: rear axle ABS on the right side, ESP, ASR.
No signal from the sensor.
Check sensor (B122) for open circuits and short circuits.
Check sensor resistance (B122) (950 - 1930 Ohm).
Check wiring and connector contacts between the pressure modulation module (Y264) and the sensor (B122).
If no fault is found, replace the EBS control unit (A402).