PI89: Stoplight Switch

This input comes through the data link from the EBTCM. PI89 should be LO with brake pedal released and HI with brake pedal depressed.

Fig 1: Identifying Red PCM Harness Connector

Courtesy of GENERAL MOTORS CORP.

Fig 2: Identifying White PCM Harness Connector

Courtesy of GENERAL MOTORS CORP.

Fig 3: Identifying Blue PCM Harness Connector

Courtesy of GENERAL MOTORS CORP.

NOTE: All PCM specific output tests are to be performed with key on, engine off.

PCM OUTPUTS option provides ability to cycle PCM-controlled outputs. DIC display identifies solenoid or relay and state PCM is commanding that device. HI indicates solenoid or relay is de-energized and LO indicates solenoid or relay is energized. See Figure .