ABS Module - Modified Scan Tool Hookup

NO.: 05-05-93
GROUP: Brakes
DATE: Mar. 5, 1993

SUBJECT:
ABS Diagnostics

MODELS:

1989-1990 (XJ) Cherokee

DISCUSSION:

The ABS module used for 1989 and 1990 vehicles (P/N 56004028) has been superseded to the 1991 module (P/N 56004948).

The 1991 module functions identically to the prior module with the exception of the method used to communicate with the Scan Tool (DRB II). This condition can be corrected by jumping across two wires in the diagnostic connector. This will allow the Scan tool to operate with the adapter, just as if it were being used on the original module.

In situations where the early ABS module has been replaced with the 1991 module, the scan tool will display "NO SERIAL DATA" when ABS diagnostics have been requested. If the " NO SERIAL DATA" display is encountered, remove the D1 diagnostic connector (smaller of the two) from the bracket by depressing the plastic retainers. Install the jumper wire at the rear of the diagnostic connector across pins 3 and 4 as shown.

The scan tool will now function normally.





If the "NO SERIAL DATA" display still exists, there may be problems with the vehicle wiring or the ABS module.

POLICY:
Information Only