Input

When troubleshooting a malfunction, the Electronic Control Module (ECM), Body Control Module (BCM), or Instrument Panel Cluster (IPC) input display can be used to determine if the switched inputs can be properly interpreted.

When one of the various input tests is selected, the state of that device is displayed as "Hi" or "LO". in general, the "HI" and "LO" refer to the input terminal voltage for that circuit. The display also indicates if the input changed state so that the technician can activate or deactivate any listed device and return to the display to see if it changed state.

If a change of state occurred, an "X" will appear next to the HI/LO indicator, otherwise a "O" will remain displayed. The "X" will only appear once per selected input, although the HI/LO indication will continue to change as the input changes. Some tests are momentary and the "X" can be used as an indication of a change.

The following is a list of BCM inputs:
BI01 The courtesy lamp panel switch display is "LO" when courtesy lights are on from switch.

BI02 The park lamp switch display is "LO" when the parklamp switch is in the off position.

BI03 The driver (front) door ajar switch display is "LO" when the driver's (front) door is ajar.

BI04 The passenger (rear) door ajar switch display is "LO" when the passengers (rear) door is ajar.

BI05 The door jamb switch display is "LO" when any door is open.

BI06 The door handle switch display is momentarily "LO" when either front outside door handle button is depressed.

BI07 The trunk open switch display is "LO" when the trunk is open.

BI08 The low refrigerant pressure switch display is "LO" when the system is low on refrigerant.

BI09 The washer fluid level switch display is "LO" when the vehicle is low on washer fluid.

B124 "PRND321" - Indicates status of reverse input, circuit 24. Should be "HI" with vehicle in reverse.


BI30 The TEMP/TIME switch display is "LO" when the button is depressed.

BI41 The cooling fan feedback display is "LO" when the cooling fans are running.

BI51 The generator feedback display is LO when there is a generator problem (or engine not running).

B171 The CRUISE CONTROL BRAKE SWITCH display is "HI" when the cruise ON/OFF switch is "ON" and the brake pedal is not depressed (free state).

B175 The CRUISE CONTROL ON/OFF SWITCH display is "HI" when the switch is "ON".

B176 The CRUISE CONTROL SET/COAST SWITCH display is "HI" when the cruise ON/OFF switch is ON and the set/coast switch is depressed.

B177 The CRUISE CONTROL RESUME/ACCEL SWITCH display is "HI" when the cruise ON/OFF switch is"ON" and the RESUME/ACCEL SWITCH is pushed.