Brake Release Switch Check
- On PCM controlled cruise control systems, install Tech 1 scanner. Turn ignition switch to ON position. Set cruise control switch to ON position. Scanner should read brake switch input as NO with brake pedal released and YES with brake pedal depressed.
- If brake release switch status is incorrect on scanner, probe circuit No. 397 (Gray) wire with a test light to ground. See Fig 1 - Fig 3
. If test light does not light, go to Fig 2 chart.
- If test light illuminates using a jumper wire, jump between Gray and Brown wires on brake release switch. If scanner status changes from NO to YES as wires are connected, adjust and/or replace brake release switch. If status on scanner does not change when wires are jumpered, check for open or short circuit No. 86 (Brown) wire between brake release switch and PCM, a poor connection at PCM or a faulty PCM.
Courtesy of GENERAL MOTORS CORP.
Courtesy of GENERAL MOTORS CORP.
Courtesy of GENERAL MOTORS CORP.