GM Service Manual Online
For 1990-2009 cars only

Body Control Module (BCM)

Battery Voltage: Display indicates battery voltage. Measured in volts.

Brake Applied Output Signal: Displays ON/OFF status of the brake pedal switch.

Ignition 1 Signal: Display indicates ON when the ignition 1 input circuit of the module receives a battery signal from the ignition switch.

Remote Start: Display indicates the current status of the remote start request.

Shift Lock Solenoid Command: Displays indicate OFF when the brake switch is depressed.

Shifter Unlock Command: Displays indicates ON when the brake switch is depressed.

Engine Control Module (ECM)

Current Gear: Displays current gear position of the transmission.

TCC Brake Switch: Displays ON or OFF status of the TCC Brake switch.

TR Sw. A/B/C/P: Displays LOW or HI for the state of each of the 4 inputs from the IMS. LOW displayed indicates a low voltage signal (0 volts) being monitored at the ECM. HI displayed indicates a high voltage signal (B+) being monitored at the ECM.