B1375 - HVAC Systems - Automatic
DTC B1375
CIRCUIT DESCRIPTION
The ignition 3 voltage circuit is a discrete input to the HVAC control module. The HVAC control modules uses the input to determine that the ignition switch is in the RUN position. When the ignition switch is in the RUN position, ignition voltage is applied to the input.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B1375 Device Ignition 3 Circuit
CONDITIONS FOR RUNNING THE DTC
- Source voltage is 8.7-16.5 volts.
- The HVAC control module receives a RUN power mode message from the BCM over the class 2 serial data circuit.
CONDITIONS FOR SETTING THE DTC
The HVAC control module does not detect ignition voltage on the ignition 3 voltage input.
ACTION TAKEN WHEN THE DTC SETS
The HVAC control module will continue to operate using the class 2 power mode messaging.
CONDITIONS FOR CLEARING THE DTC
- The DTC will become history if the HVAC control module no longer detects the condition that set the DTC.
- The history DTC will clear after 100 fault free ignition cycles.
- The DTC can be cleared with a scan tool.
TEST
