A015

Diagnostic Chart:

CIRCUIT DESCRIPTION
The sunload sensor uses a light sensitive photodiode to control the signal voltage to the ACP. This photodiode is different from standard thermistor type sensors and resistance measurements will not produce accurate results. The ACP monitors the voltage on CKT 590 to the sensor. When the sensor is in direct light the ACP will see a low signal voltage. As the sensor becomes shaded, the signal voltage increases. This signal voltage will vary between 5V (open circuit) and 0V (short circuit).

TEST CONDITION(S)
1. Ignition "ON."

FAILURE CONDITION(S)
The signal voltages indicates less than 2% (short circuit) or greater than 98% (open circuit).

ACTION TAKEN
1. A substitute reading (98%) will be implemented to allow continued operation of the climate control system.
2. The sunload temperature reading AD32 will display the actual sensor reading.

NOTES ON FAULT TREE
1. ACP data value AD32 displays sunload reading. The normal range is from 2 to 98%.
2. A reading too high indicates an open circuit. Jumpering the harness connector will determine whether the wiring or sensor is the cause of the open.
3. A reading too low indicates a short circuit. Removing the sensor will determine whether the wiring or sensor is the cause of the short.
4. The open has been determined to be in the wiring. Providing a ground at the jumper will determine if the open is in the ground wiring or the sensing wire.
5. Grounding the connector at the ACP will determine if the open is in the sense circuit or at the ACP connection/ACP internal.
6. If A015 is set without A013, look for an open CKT 407 between 5241 and the sensor. (An open anywhere else in the circuit should set at least A013 as well.)

NOTES ON INTERMITTENTS
If an intermittent code A015 is being set, select ACP Snapshot Data for Code A015 and note value of AD32. A reading of approx 98% indicates an intermittent open, a reading below 2% indicates an intermittent short.

Manipulate the related wiring while observing ACP data AD32. If the failure is induced, the reading will jump outside its normal range.