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B0977




DTC B0977

Circuit Description

The ignition mode switch has three LEDs that indicate the vehicle power mode. When the vehicle is in the Off mode, the Off LED may illuminate. Pressing the lower button of the ignition mode switch, the vehicle enters the accessory mode and ACC LED will illuminate. Keeping the lower button pressed for about 5-6 seconds, the vehicle enters run mode with the engine off and the START LED will illuminate. All these LEDs have the voltage supplied from the BCM through the ignition mode switch supply voltage circuit. The ground path for each LED is controlled by the BCM.

DTC Descriptors
This diagnostic procedure supports the following DTCs:

^ DTC B0976 Off Indicator Control Circuit
^ DTC B0977 Start Indicator Control Circuit
^ DTC B0978 Accessory Indicator Control Circuit

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description in Vehicle DTC Information.







Conditions for Running the DTC
Voltage supplied to the module is in the normal operating voltage range of 9-16 volts.

Conditions for Setting the DTC

B0976 01
^ The BCM detects a short to battery in the off indicator control circuit.
^ The above condition exists for more than 5 seconds.

B0977-B0978 01
^ The BCM detects a short to battery in the respective indicator control circuit, when the output is active.
^ The above condition exists for more than 1 second.

B0976-B0978 06
^ The BCM detects an open or short to ground in the respective indicator control circuit, when the output is inactive.
^ The above condition exists for more than 1 second.

Action Taken When the DTC Sets

B0976-B0978 01
The BCM disables the respective output until the next ignition cycle.

Conditions for Clearing the DTC
^ A current DTC clears when the malfunction is no longer present.
^ A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Test Description
The numbers below refer to the step numbers on the diagnostic table.

3. If more than one DTC were retrieved, the fault condition is common for all circuits.
7. A LED that illuminates, assures that the fault is not internal to the ignition mode switch.
8. A B0976 requires vehicle in OFF mode, a B0977 requires ignition ON with the engine OFF and a B0978 requires vehicle in accessory mode.