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Rear Wheel Anti-Lock Brakes - Trouble Code 7


91chevy12

Number: 91-254-5

Section: 5

Date: March 1991

Corp. Bulletin No.: 165005


Subject: REAR WHEEL ANTI-LOCK BRAKE (RWAL) CODE 7


Model and Year: 1988-91 ALL LIGHT DUTY TRUCKS WITH RWAL


After a repair has been made to the RWAL system on light duty trucks, technicians will need to clear codes and check for reoccurrence in order to verify the repair. To clear the stored codes, technicians must turn the ignition to the OFF position and remove the ECU memory power fuse (Stop/Hazard fuse on C/K and RN trucks, Horn/Dome fuse on M series vans, Tail LPS fuse on G Vans, and ECM B fuse on S/T trucks). If the ignition switch is not turned to the OFF position, the ECU could be permanently damaged and a code 7 may be set. If this occurs it will not be possible to clear the code and the ECU will have to be replaced.