Circuit Description
The ambient light sensor is a light sensitive diode. The instrument panel integration module (IPM) determines the ambient light based on the voltage from the ambient light sensor. The IPM sends out a class 2 message to the dash integration module (DIM).
Conditions for Running the DTC
This test is run every 150 milliseconds.
Conditions for Setting the DTC
The ambient light sensor voltage is less than 0.09 or greater than 4.75V on 3 consecutive tests.
Action Taken When the DTC Sets
Ambient light status set to "DARK".
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.
Diagnostic Aids
| • | The following may cause an intermittent: |
| - | Bent terminal |
| - | Backed out terminal |
| - | Damaged terminal |
| - | Poor terminal tension |
| - | Chafed wire |
| - | Broken wire inside the insulation |
| • | When diagnosing for an intermittent short or an open, manipulate the wire harness while watching the test equipment for changes. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Tests for the proper operation of the circuit in the high voltage range.
-
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.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Lighting Systems Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate that the Ambient Light Sensor data parameter is within the specified range? | 0.09-4.8 V | Go to Diagnostic Aids | Go to Step 3 |
Does the scan tool indicate that the Ambient Light Sensor data parameter is greater than the specified value? | 4.8 V | Go to Step 4 | Go to Step 5 | |
Does the scan tool indicate that the Ambient Light Sensor data parameter is less than the specified value? | 0.09 V | Go to Step 8 | Go to Step 6 | |
5 | Test the signal circuit of the ambient light sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 |
6 | Test the signal circuit of the ambient light sensor for a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 7 |
7 | Test the sensors return circuit of the ambient light sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 |
8 | Inspect for poor connections at the harness connector of the ambient light sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
9 | Inspect for poor connections at the harness connector of the instrument panel integration module (IPM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 |
10 | Replace the ambient light sensor. Refer to Sun Load Sensor Replacement in HVAC Systems - Automatic. Did you complete the replacement? | -- | Go to Step 12 | -- |
11 | Replace the instrument panel integration module (IPM). Refer to Instrument Panel Module Replacement in Body Control. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
