Bosch ABS 2U - Diagnostic Codes for EF/EL Falcon Fairmont, XR, Fairlane and LTD Models
This document describes the ABS Error codes for the Bosch ABS 2U model, which was fitted to Ford EF and EL Models,
Ford Falcon, Fairmont, Fairlane, LTD, and XR series vehicles
This information includes how to place the ABS into diagnostic mode, and how to read the codes without using a Diagnostic connector
About the ABS Diagnostic Mode
The Bosch ABS 2U system, has a self test facility, and will hold intermittent faults within its memory, for a period of 250 Key Starts.
Fault codes are classified as being either on demand, i.e. present at the time of the self test, or stored, i.e. occurred previously and have since been repaired and intermittent faults.
Upon detecting a fault, the ECU will shut the ABS system down, the Check ABS light will illuminate, and the Fault will be logged.
After one ignition cycle and if the fault has been rectified, the ABS system will again be operational, and will log the fault as a stored code.
Once the system has shut down, it will not recover until the ignition has been cycled.
Up to 3 codes can be logged simultaneously, and can be viewed sequentially. For this reason, it is important that the system is retested once a problem has been rectified, to ensure that no further fault codes exist.
Entering Diagnostic Mode
The Diagnostic connector is located behind the fuse box panel cover (underneath the Instrument panel, on the right of the steering column).
The ABS module can be entered into diagnostic mode by grounding the ABS STI (Self Test Input) pin, on the Vehicles Diagnostic connector.
This can be achieved by connecting the ABS GND pin (3rd pin from left, second row), to the ABS STI pin (3rd pin from left, upper row).
Once the ABS Module has been placed in to Diagnostic mode, the Check ABS Light on the Instrument Panel will flash, giving the ABS Trouble code.
Clearing ABS Diagnostic Fault Codes
The ABS ECU Self test codes are held in the EEPROM, and can only be cleared by performing a self test procedure, interrupting the self test during code display (i.e. removing the Ground link to the ABS STI pin), and waiting 3-5 seconds, before switching the ignition off.
Diagnostic Codes
Code
Name
Description
Action Required
12
No ABS Fault codes Stored
System OK (as far as self test can determine)
19
ABS ECU Fault
There is an internal fault with the ABS ECU. The ECU Must be Replaced
Replace ABS ECU, and retest system
22
Right Front Valve Fault (Drivers Side)
There is a fault in the Solenoid, The ABS Modulator unit must be replaced
Replace ABS Modulator, and retest system
24
Left Front Valve Fault (Passenger Side)
There is a fault in the Solenoid, The ABS Modulator unit must be replaced
Replace ABS Modulator, and retest system
26
Rear Valve Fault
There is a fault in the Solenoid, The ABS Modulator unit must be replaced
Replace ABS Modulator, and retest system
31
Right Front wheel speed sensor continuity fault (Drivers Side)
The ABS Speed sensor is open circuit. The fault could lie in either the sensor, wiring, or ECU
Perform Test 1 - Test Speed sensor, and wiring loom for speed sensor
32
Right Rear wheel speed sensor continuity fault (Drivers Side)
The ABS Speed sensor is open circuit. The fault could lie in either the sensor, wiring, or ECU
Perform Test 1 - Test Speed sensor, and wiring loom for speed sensor
33
Left Front wheel speed sensor continuity fault (Passenger Side)
The ABS Speed sensor is open circuit. The fault could lie in either the sensor, wiring, or ECU
Perform Test 1 - Test Speed sensor, and wiring loom for speed sensor
34
Left Rear wheel speed sensor continuity fault (Passenger Side)
The ABS Speed sensor is open circuit. The fault could lie in either the sensor, wiring, or ECU
Perform Test 1 - Test Speed sensor, and wiring loom for speed sensor
41
Right Front wheel speed sensor fault (Drivers Side)
The sensor signal is wrong for the current vehicle conditions. The fault could be in the sensor, the wiring, or the ECU. The tone wheel may be missing, or the wrong type fitted. The Sensor may have fallen out.
Perform Test 2 - Test Speed sensor, and wiring loom for speed sensor
42
Right Rear wheel speed sensor fault (Drivers Side)
The sensor signal is wrong for the current vehicle conditions. The fault could be in the sensor, the wiring, or the ECU. The tone wheel may be missing, or the wrong type fitted. The Sensor may have fallen out.
Perform Test 2 - Test Speed sensor, and wiring loom for speed sensor
43
Left Front wheel speed sensor fault (Passenger Side)
The sensor signal is wrong for the current vehicle conditions. The fault could be in the sensor, the wiring, or the ECU. The tone wheel may be missing, or the wrong type fitted. The Sensor may have fallen out.
Perform Test 2 - Test Speed sensor, and wiring loom for speed sensor
44
Left Rear wheel speed sensor fault (Passenger Side)
The sensor signal is wrong for the current vehicle conditions. The fault could be in the sensor, the wiring, or the ECU. The tone wheel may be missing, or the wrong type fitted. The Sensor may have fallen out.
Perform Test 2 - Test Speed sensor, and wiring loom for speed sensor
Check that ABS ECU is connected to power, and ground. Replace ECU.
69
Voltage Fault
The ECU has detected a low supply voltage. The cause could be alternator, battery, wiring or the ECU
Check Power wiring to ABS ECU for any faults, re-test.
78
ABS Operation error
While the ABS was operating, road conditions caused incompatible wheel speed signal errors. Usually caused by doing burnouts and line locks. Erase code and Road Test.
Inspect tone wheels for missing teeth, or run out. Replace faulty tone wheels
ABS Test 1
1) Is the Wheel speed sensor connected. If not connect wheel sensor and re-test
2) Is the Wheel sensor resistance 1.2KOhm +- 0.2KOhm (Front Sensors) - 2.2KOhm +- 0.4KOhm (Rear Sensors). If not, replace sensor, and Re-test.
3) Repair Wiring loom, and re-test
ABS Test 2
1) Is the Wheel speed sensor securely attached. If not, then secure and re-test
2) Is the correct tone wheel in place. If not, fit correct tone wheel, and re-test
3) Inspect tone wheel, and run out. If tone wheel faulty, replace, and re-test
4) Is sensor connected. If not, re-connect sensor, and re-test
5) Is sensor shorted to ground, or another sensor. If so, replace wiring loom, and re-test.
6) If problem still exists, replace wiring loom. and re-test.
