B1318

Schematic:

CIRCUIT DESCRIPTION
The LH sun load sensor is a light sensitive photodiode that controls signal voltage to the Instrument Panel Integration Module (IPM). This photodiode is different from standard thermistor sensors and resistance measurements will not produce accurate results. The IPM monitors voltage on circuit 590 to the sensor. When the sensor is in direct sun light, the IPM reads a low signal voltage at terminal B2, connector C2. When the sensor is shaded, the signal voltage increases. Signal voltage will vary from 5 V (open circuit) to 0 V (short circuit).

CONDITIONS FOR SETTING THE DTC
^ The ignition is ON.
^ Circuit open or shorted.

ACTION TAKEN WHEN THE DTC SETS
^ The IPM will default the system to dark or no sun load value.
^ The default valve allows the system to operate.

CONDITIONS FOR CLEARING THE MIL/DTC
^ Using a Scan Tool.
^ A current DTC will clear when the diagnostic runs and does not fail.
^ IPM battery voltage is interrupted.

TEST DESCRIPTION

DTC B1318 LH Sun Load Sensor Fault:

The numbers below refer to the step numbers on the diagnostic table.
1. Perform the Body Control Module (BCM) Diagnostic System Check before continuing with the diagnosis of this DTC. Initial Inspection and Diagnostic Overview
2. Determines whether the sensor is operational.
3. Determines that the DTC was not set in error.
4. Determines if the malfunction is the sensor or an open or a short in a circuit.
9. Determines it the HCM or an open or short is causing the malfunction.
12. The Scan Tool checks for proper sensor operation. Clear all the DTCs after the repair procedures are complete.