B2647

Diagnostic Chart:

Schematics:

CIRCUIT DESCRIPTION
The twilight photocell sensor is a light sensitive photocell. The climate control panel (CCP) determines the ambient light based on the voltage from the twilight photocell sensor. The CCP controls the head lamp automatic on/off, delayed off functions.

CONDITIONS FOR RUNNING THE DTC
Enable flag is set to enable.
DTC B1327 is not current.
The CCP is powered.

CONDITIONS FOR SETTING THE DTC
The twilight photocell voltage is less than 0.2 V. The above condition is present for greater than 2 seconds.

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

CONDITIONS FOR CLEARING THE MIL/DTC
The CCP does not detect a voltage less 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.