ABS - Repeated Code 4 (Grounded Valve Reset Switch)
90chevy15GMC NUMBER: 90-5E-71
GROUP: 5E Anti-Lock Brakes
DATE: June 1990
CORPORATE
NUMBER: 065002R
SUBJECT: REPEATED CODE 4 (GROUNDED VALVE RESET SWITCH CIRCUIT)
MODELS: 1990 G VANS
Incidents of repeated code 4, conditions may be observed on the above vehicles. This condition can be caused by contamination of the dual coil electrical connector which is part of the RWAL control valve assembly. The contamination can cause a short to ground within the connector resulting in a code 4 being set and deactivation of the anti-lock feature of the RWAL System.
A new dual coil connector has been released which prevents water and contamination intrusion into the connector. The new connector can be identified by its natural whitish/yellow color. All previous connectors have been black.
Figure No. 1 - G Van Assembly Illustrated:
Important
The dual coil connector is manufactured as an integral component of the RWAL control valve assembly therefore the control valve must be replaced as a unit (see Figure 1).
RWAL Trouble Code 4 Diagnosis Chart:
DIAGNOSIS INFORMATION Technicians should refer to RWAL Update 4WAL Preview manual 15005.05-1 mailed under cover bulletin 90-5E-07 (October 1989) tor correct diagnostic procedures. If the connector is the cause of the code 4, the manual will identify the control valve assembly as the probable cause. (See attached Code 4 diagnosis chart).
When the control valve has been replaced the technician should clear all codes, and assure that no other codes are set by performing a function test and Diagnostic Circuit Check.
Figure No. 2:
Important
The wiring diagram for control valve to the ECU is given in Figure 2. This diagram shows the correct wire/color sequence and connections.
PARTS INFORMATION
Parts are currently available through GMSPO.
WARRANTY INFORMATION For vehicles repaired under warranty use:
Labor Operation: H2480
Labor Time: Use time as indicated in the labor time guide.