The following DTCs are for the left and right sunload sensors:
• | B0183 is for the left sunload sensor. |
• | B0188 is for the right sunload sensor. |
The left and right sunload sensors provide the HVAC control module with inputs as to the amount heat load the sun is placing on the interior of the vehicle. The sunload sensors are photodiodes that are sensitive to light intensity. The body control module (BCM) applies 5 volts to internal input resistors that are connected to the left and right signal circuits of the sunload sensor assembly. The BCM provides ground to the sensors through the low reference circuit. The BCM monitors the voltage drops across the sunload sensors and converts the voltage values to count values where 1 volt is approximately equal to 51 counts. As the light intensity increases, the sunload sensors allow more current to travel through the circuits and the signal voltages decrease. As the light intensity decreases, the sunload sensors allow less current to travel through the circuits and the signal voltages increase. The BCM transmits the data to the HVAC control module over the class 2 serial data circuit.
This diagnostic procedure supports the following DTCs:
• | DTC B0183 Solar Load Sensor Left Circuit |
• | DTC B0188 Solar Load Sensor Right Circuit |
The ignition is ON.
The BCM determines that the value of the sunload sensor signal is less than 5 counts or greater than 250 counts.
The action taken will be for the BCM to revert to a calibrated default value.
• | The DTC will become history if the BCM no longer detects a failure. |
• | The history DTC will clear after 100 fault-free ignition cycles. |
• | The DTC can be cleared with a scan tool. |
The numbers below refer to the step numbers on the diagnostic table.
This step verifies that the value displayed is within the specified range.
This step tests for the proper operation of the circuit in the high voltage range.
This step 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 |
---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the scan tool indicate that the appropriate Solar Sensor parameter is within the specified range? | 5-250 Counts | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | |
Does the scan tool indicate that the appropriate Solar Sensor parameter is greater than the specified value? | 250 Counts | Go to Step 4 | Go to Step 5 | |
Does the scan tool indicate that the appropriate Solar Sensor parameter is less than the specified value? | 5 Counts | Go to Step 8 | Go to Step 6 | |
5 | Test the appropriate solar signal circuit of the sunload sensor assembly 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 appropriate signal circuit of the sunload sensor assembly 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 low reference circuit of the sunload sensor assembly 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 sunload sensor assembly. 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 BCM. 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 sunload sensor assembly. Refer to Sun Load Sensor Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- |
11 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK |