• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Left Solar Load Sensor Signal | B0184 | B0184 | B0184 | -- |
Right Solar Load Sensor Signal | B0189 | B0189 | B0189 | -- |
Low Reference | B0184, B0189 | B0184, B0189 | B0184, B0189 | -- |
The sunload sensor is a 2-wire photo diode. The vehicle uses left and right sunload sensors. The two sensors are integrated into the sunload sensor assembly along with the ambient light sensor. Low reference and signal circuits enable the sensor to operate. As the sunload increases, the sensor signal decreases. The sensor operates within an intensity range between completely dark and bright. The sensor signal varies between 0-5 volts. The HVAC control module converts the signal to a range between 0-255 counts. The sunload sensor provides the HVAC control module a measurement of the amount of light shining on the vehicle. Bright or high intensity light causes the vehicles inside temperature to increase. The HVAC system compensates for the increased temperature by diverting additional cool air into the passenger compartment when in the Auto mode.
The ignition is ON.
The HVAC control module detects the signal circuit is less than 0.09 volt (5 counts) or more than 4.90 volts (250 counts).
If the DTC sets due to a low voltage condition, the HVAC control module will operate the system as if a maximum sunload condition exists. If the DTC sets due to a high voltage condition, the HVAC control module will operate the system as if a minimum sunload condition exists.
• | The DTC will become history if the HVAC control module no longer detects the condition that set the DTC. |
• | The history DTC will clear after 50 fault-free ignition cycles. |
Control Module References for scan tool information
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal replace the HVAC control module. |
⇒ | If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the HVAC control module. |
⇒ | If not the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the HVAC control module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the HVAC control module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the HVAC control module. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for HVAC control module replacement, setup, and programming |