RWAL/4WAL Brakes - Clearing Trouble Codes
91chevy16
GMC NUMBER: 91-5E-84
GROUP: 5E Antilock
DATE: April, 1991
CORPORATE
NUMBER: 165001
SUBJECT: CLEARING RWAL/4WAL TROUBLE CODES
MODELS: ALL 1990-91 M/L VANS AND S/T 4 DOOR UTILITY VEHICLES EQUIPPED WITH FOUR WHEEL ANTILOCK (4WAL) BRAKE SYSTEMS
Some technicians may experience difficulty in clearing stored codes when using the Tech One scan tool after repairs have been performed on 4WAL systems. If this occurs the ignition should be cycled off for 5 seconds and then technicians should attempt to clear the code(s) again. It may be necessary to cycle the ignition in this manner several times before the codes will clear.
Once cleared, a function test of the system along with a road test should be made to verify that the repair was made correctly and the codes do not RESET.
Note: Use of the Tech One tool is highly recommended (refer to GMC Truck Service Bulletin 91-5E-74; Corporate Number 165003).