Pci Bus Loopback - Jeep KJ Liberty 2005 Service Manual

Symptom:

PCI BUS LOOPBACK

When Monitored and Set Condition:
PCI BUS LOOPBACK
When Monitored: Ignition On - Continuously
Set Condition: When the ABM detects PCI Bus messages have been missing for 5 seconds
and has failed the self test.
INTERMITTENT DTC
DAMAGED ABM/ABM HARNESS CONNECTOR
FUSED RUN RELAY OUTPUT CIRCUIT OPEN
ABS VALVE FUSED B(+) CIRCUIT OPEN
ABM - GROUND CIRCUIT OPEN
ABM - INTERNAL FAULT
TEST
1 Turn the ignition on.
With the DRBIII , read DTCs.
With the DRBIII , erase DTCs.
Turn the ignition off.
Turn the ignition on.
With the DRBIII , read DTCs.
Does the DRBIII display PCI BUS LOOPBACK?
Yes → Go To 2
→ Go To 6
No
2 Turn the ignition off.
Disconnect the ABM harness connector.
Inspect the ABM/ABM harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?
Yes → Repair as necessary.
→ Go To 3
No
3 Turn the ignition off.
Disconnect the ABM harness connector.
Turn the ignition on.
Measure the voltage of the Fused Run Relay Output circuit.
Is the voltage above 10 volts?
Yes → Go To 4
→ Repair the Fused Run Relay Output circuit for an open.
No
POSSIBLE CAUSES
ACTION
Perform ABS VERIFICATION TEST - VER 1.
Perform ABS VERIFICATION TEST - VER 1.
31
BRAKES (25E)
APPLICABILITY
All
All
All