For 1990-2009 cars

### Body Control Module (BCM)

Battery 1: Displays 0.0-25.5 V. This parameter is the system voltage measured by the BCM at the BCM battery input.
Brake to Shift Relay: Displays ON/OFF. This parameter indicates ON when the mechanical lock is engaged preventing an inadvertent shift out of the PARK position. The Display indicates OFF when BCM opens the controlled voltage circuit of the shift lock control solenoid.

### Engine Control Module (ECM)

Battery 1: Displays 0.0-25.5 V. This parameter is the system voltage measured by the BCM at the BCM battery input.
TCC Brake Switch: Displays ON/OFF. This parameter indicates ON when the brake pedal is depressed and OFF when the brake pedal is released.