DTC 05

CIRCUIT DESCRIPTION
The sun load sensor assembly is a reverse bias photodiode which measures sun load on the vehicle. In "AUTO" mode, the sensor is an input to the H-A/C control to control air delivery. In bright sunlight, the influence of the sensor is comparable to lowering the guide temperature setting by as much as three degrees. A current DTC 05 will be set if an open exists in the circuit.

DTC WILL SET WHEN
With ignition is "RUN," the H-A/C control will detect this fault anytime that CKT 590 stays at or near 5V or higher.

ACTION TAKEN:
DTC 05 will set in the H-A/C control. While the DTC is present, the H-A/C control will use a default value of 240 (readout shows "-140") which is equivalent to no sun load. This can be seen by displaying pointer "-18" for the sun load sensor.

DTC WILL CLEAR WHEN
This fault will clear as soon as the fault has been repaired. The system will return to normal operation.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks for HVAC DTC(s) and should clear any intermittent DTC(s).
2. This test checks for normal to above voltage on CKT 590.
3. This test checks for an open in CKT 198.

DIAGNOSTIC AIDS
Visually inspect sensor and connector damage by removing grille assembly.