Circuit Description
The following DTCs are for the internal fluid temperature sensors located internal to the starter/generator control module (SGCM):
| • | P0A01 is for the internal fluid temperature sensor 1 performance. |
| • | P0A02 is for the internal fluid temperature sensor 1 high temperature. |
| • | P0A03 is for the internal fluid temperature sensor 1 low temperature. |
| • | P1A7A is for the internal fluid temperature sensor 3 low temperature. |
| • | P1A75 is for the internal fluid temperature sensor 2 performance. |
| • | P1A76 is for the internal fluid temperature sensor 2 high temperature. |
| • | P1A77 is for the internal fluid temperature sensor 2 low temperature. |
| • | P1A78 is for the internal fluid temperature sensor 3 performance. |
| • | P1A79 is for the internal fluid temperature sensor 3 high temperature. |
The SGCM monitors its internal fluid temperature sensors to control the SGCM coolant pump and SGCM cooling fan. The internal fluid temperature sensors of the SGCM are thermistors and are not serviceable. When the internal fluid temperatures are cold, the resistances of the sensors are high and the voltage signals are high. When the internal fluid temperatures are hot, the resistances of the sensors are low and the voltage signals are low. The input parameters are not displayed on the scan tool.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC P0A01 Starter/Generator Control Module Coolant Temperature Sensor 1 Performance |
| • | DTC P0A02 Starter/Generator Control Module Coolant Temperature Sensor 1 Circuit Low Voltage |
| • | DTC P0A03 Starter/Generator Control Module Coolant Temperature Sensor 1 Circuit High Voltage |
| • | DTC P1A7A Starter/Generator Control Module Coolant Temperature Sensor 3 Circuit High Voltage |
| • | DTC P1A75 Starter/Generator Control Module Coolant Temperature Sensor 2 Performance |
| • | DTC P1A76 Starter/Generator Control Module Coolant Temperature Sensor 2 Circuit Low Voltage |
| • | DTC P1A77 Starter/Generator Control Module Coolant Temperature Sensor 2 Circuit High Voltage |
| • | DTC P1A78 Starter/Generator Control Module Coolant Temperature Sensor 3 Performance |
| • | DTC P1A79 Starter/Generator Control Module Coolant Temperature Sensor 3 Circuit Low Voltage |
Conditions for Running the DTC
| • | The engine has been running for 30 seconds. |
| • | The SGCM has received voltage on the ignition 0 voltage circuit. |
| • | The SGCM has turned ON and no configuration DTC are present. |
Conditions for Setting the DTC
| • | For low temperature DTC the monitored internal fluid temperature of the sensor is below -40°C (-40°F). |
| • | For high temperature DTC the monitored internal fluid temperature of the sensor is above 125°C (257°F) |
| • | For performance DTC the monitored average internal fluid temperature of the sensor is 15°C (27°F) different than average of the all internal fluid temperature sensors. |
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
| • | The driver information center, if equipped, may display a message. |
Conditions for Clearing the DTC
| • | A current DTC Last Test Failed clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | Clear the DTC with a scan tool. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Cooling Schematics Connector End View Reference: Cooling System Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Is the DTC set as current DTC? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections |
3 | With a scan tool, command the cooling fan ON and OFF. Does the cooling fan turn ON and OFF with each command? | Go to Step 4 | Go to Cooling Fan Inoperative |
4 | With a scan tool, command the SGCM Coolant Pump ON and OFF. Does the SGCM coolant pump turn ON and OFF with each command? | Go to Step 5 | Go to Starter Generator Control Module Coolant Pump Inoperative |
5 | Inspect for poor connections at the harness connector of the SGCM . Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 6 |
6 | Replace the SGCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
