B2646

Diagnostic Chart:

Schematics:

CIRCUIT DESCRIPTION
The twilight photocell sensor is a light sensitive diode. The Instrument Panel Module determines the ambient light based on the voltage from the twilight photocell sensor. The IPM sends out a class 2 message to the dash integration module.

CONDITIONS FOR RUNNING THE DTC
The IPM is powered.

CONDITIONS FOR SETTING THE DTC
The twilight photocell voltage is less than 0.09 or greater than 4.75V.

ACTION TAKEN WHEN THE DTC SETS
The IPM sets the variable ambient light status to status set to DARK.
The IPM sets a DTC.

CONDITIONS FOR CLEARING THE MIL/DTC
The IPM does not detect a voltage that is less than or greater than the predetermined value during the diagnostic self test.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
3. Tests for the proper operation of the circuit in the high voltage range.
4. Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.