P0A01

DTC P0A01-P0A03

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptors
DTC P0A01
- Motor Electronics Temperature Sensor Circuit Range/Performance

DTC P0A02
- Motor Electronics Temperature Sensor Circuit Low

DTC P0A03
- Motor Electronics Temperature Sensor Circuit High

Diagnostic Fault Information





Circuit/System Description

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.

Conditions for Running the DTC

P0A01
* 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.

P0A02
* 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.

P0A03
* 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.

Conditions for Setting the DTC

P0A01

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).

P0A02

The ECM detects that the generator control module temperature sensor parameter is less than -60.5°C (-76.9°F).

P0A03

The ECM detects that the generator control module temperature sensor parameter is greater than 162°C (323.6°F).

Action Taken When the DTC Sets

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

Conditions for Clearing the MIL/DTC

* 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.

Reference Information
Schematic Reference

HVAC Schematics (HVAC - Manual)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

* Air Temperature Description and Operation (Air Temperature Description and Operation)
* Air Delivery Description and Operation (Air Delivery Description and Operation)

Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Engine running, observe the scan tool DMCM Coolant Temperature Signal parameter. The reading should be between -61 to +161°C (-78 to +321F) depending on the current ambient temperature and the vehicle operating conditions.
2. Operate the vehicle within the Conditions for Running the DTC.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the generator control module temperature sensor.
2. Ignition OFF for 90 seconds, test for less than 5 ohms between the low reference circuit terminal A and ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, verify the scan tool DMCM Coolant Temperature parameter is greater than 162°C (323°F).

• 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.

4. Install a 3A fused jumper wire between the signal circuit terminal B and ground. Verify the scan tool DMCM Coolant Temperature parameter is less than -60.5°C (-76.9°F).

• 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.

5. If all circuits test normal, test or replace the generator control module temperature sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Coolant Temperature Sensor Replacement (Generator Control Module) (Coolant Temperature Sensor Replacement (Generator Control Module))
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming