| • | 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  | High Resistance  | Open  | Short to Voltage  | Signal Performance  | 
|---|---|---|---|---|---|
Generator Control Module Temperature Sensor Signal  | P0A02  | P0A03  | P0A03  | P0A03  | P0A01  | 
Low Reference  | --  | P0A03  | P0A03  | P0A03  | P0A01  | 
The generator control module temperature sensor is a variable resistor that measures the temperature of the coolant entering the generator control module coolant radiator. The engine control module (ECM) supplies 5 volts to the generator control module temperature signal circuit, and a ground for the generator control module temperature low reference circuit.
| • | DTCs P0112, P0113, P0117, P0118, P0101, P0102, P0103, P0A02, P0A03 and P2610 are not set. | 
| • | The ignition has been OFF for greater than 8 hours. | 
| • | The temperature difference between the IAT and ECT sensors is less than or equal to 16°C (29°F) at ignition ON. | 
| • | DTCs P0112 or P0113 are not set. | 
| • | The engine is running for greater than 10 seconds. | 
| • | The Intake Air Temperature Sensor (IAT) is greater than 70°C (158°F). | 
| • | This DTC runs continuously when the above conditions are met. | 
| • | DTCs P0112 or P0113 are not set. | 
| • | The engine is running for greater than 10 seconds. | 
| • | The IAT is greater than -20°C (-04°F). | 
| • | This DTC runs continuously when the above conditions are met. | 
The ECM detects that the temperature difference between the generator control module temperature sensor parameter and the ECT sensor is greater than 30°C (54°F).
The ECM detects that the generator control module temperature sensor parameter is less than -60.5°C (-76.9°F).
The ECM detects that the generator control module temperature sensor parameter is greater than 162°C (323.6°F).
DTCs P0A01, P0A02 and P0A03 are Type B DTCs.
| • | The cooling fans will be commanded to high speed. | 
| • | The DIC will display A/C Inoperative | 
| • | P0A01 requires that the ECM detect that the temperature difference between the generator control module temperature sensor parameter and the ECT sensor is less than or equal to 16°C (29°F) at ignition ON. | 
| • | DTCs P0A01, P0A02 and P0A03 are Type B DTCs. | 
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 ECM. | 
| ⇒ | If less than the specified range, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the ECM. | 
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM. | 
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |