ABS - Fault Blink Code Diagnostic Procedure
27/10/9570/01/95/US
SUBJECT:
ABS Fault Blink Code Diagnostic Procedure
MODEL:
Discovery
AFFECTED VEHICLES
LP
LH
LJ TA163104 onwards
LJ TA501920 onwards
DETAIL
If diagnostic equipment is not available (i.e. there is not a current TestBook disk available) the following procedure can be carried out using the "Blink Code" method to read fault codes. Faults are stored in the ECU memory in code form, which can be retrieved by initiating and reading a series of flash and pause sequences on the ABS warning light.
ACTION REQUIRED
If diagnostic equipment is not available follow the procedure below to diagnose an ABS fault.
PARTS INFORMATION
YPJ10015 - terminal - 2 required (available in LRNA Terminal Kit).
PROCEDURE
1. Fabricate a jumper wire with YPJ10015 terminals and appropriate wire (6" length 16 gauge).
2. Locate TestBook diagnostic connector under dash. Connect jumper wire to pins 5 and 15 and turn ignition to position 2.
3. Five seconds after the ignition is turned to position 2 the Anti-Lock warning light will extinguish, indicating the start of the cycle.
4. Observe the Anti-Lock warning light, the start phase of the blink code is signified by the following:
- Pause = 2.5 secs. (long)
- Flash = 2.5 secs. (long)
- Pause = 2.5 secs. (long)
- Flash = 0.5 secs. (short)
(See Figure 1 for start phase diagram)
5. The first part of the code number is determined by a pause of 2.5 secs. which precedes a series of short flashes then a long pause. The number of short flashes is equal to the first digit in the fault code.
6. The second digit in the code number is determined after a pause of 2.5 secs. which occurs between the first and second code flashes. After the pause there will be a number of short flashes, the number of flashes is equal to the second digit in the fault code. After the flashes there will be another pause of 2.5 seconds before the system repeats the flash and pause sequence. This will allow for a verification of the code or if the initial flash and pause sequence was missed.
Figure 2 shows an example of the flash and pause sequence for code 2-2.
7. The sequence of the start phase, first and second code parts will continue until terminated by the operator. To terminate the code sequence disconnect the jumper wire.
NOTE:
Termination will clear the memory of that particular fault, and the fault will not be retrievable. Do not terminate the sequence if unsure of the code number.
8. The memory is capable of storing more than one fault. To search the memory, after the jumper wire is disconnected wait until the Anti-Lock light illuminates and then turn the ignition off, the code is now completely cleared. To obtain the next code repeat the procedure from step 2.
9. If there are no faults remaining there will be a long pause of 7.5 secs. after the start phase.
10. Once all the codes have been obtained and cleared, locate the problem cause and rectification for each code and fix accordingly.
FAULT CODE LIST
KEY: IV - Inlet Valve, OV - Outlet Value, RCP - Recirculation pump (ABS pump)
Sensor check:
1. Carry out multimeter test, check electrical resistance of sensor, this should be 700-2000 ohms. Check sensor voltage output, this should be greater than or equal to 0.93 VAC RMS when rotating the wheel at 1 rev/sec.
2. Check sensor air gap. Push sensor through bush until it touches exciter ring. Sensor will be knocked back to correct position when the vehicle is driven.
3. Check run out of the exciter ring and rectify if necessary.
4. Check bearing play and adjust if necessary.
5. Check sensor bush and exchange if necessary.
WARRANTY
Normal warranty policy and procedure apply.
COMP. CODE
Code against failure
SRO
70.58.89/26 - Obtain fault code using blink method - 00.20 hour