2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 787

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 787

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool References

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Verify DTC C056E is not set.

If the DTC is set, program the control module. If the DTC resets, replace the control module.

Repair Instructions

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

Control Module References (See: Testing and Inspection/Programming and Relearning) for control module replacement, setup, and programming

C078A

DTC C078A

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC C078A 39

- Tire Pressure Indicator Module Internal Malfunction

Circuit/System Description

The internal fault detection is handled inside the tire pressure sensor locator module. No external circuit diagnosis is involved.

Conditions for Running the DTC

The module runs the program to detect an internal fault when power up is commanded. The only requirements are voltage and ground. This

program runs even if the voltage is out of the valid operating range.

Conditions for Setting the DTC

The module has detected an internal malfunction.

Action Taken When the DTC Sets

The module refuses all additional inputs.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* This DTC may be stored as a history DTC without affecting the operation of the module.

* If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.

* If this DTC is retrieved as both a current and history DTC, replace the tire pressure sensor locator module.

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1000

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1000

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Note: If any Turbocharger circuit DTC is set, the Bypass Solenoid Valve output control may not function. It may be necessary to clear the

DTCs with a scan tool to enable the output control.

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0234, P0299, P0236, P0237, P0238, P0244, P0245, or P0246

is not set.

瀚慖f a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble

Code (DTC) List - Vehicle) for further diagnosis.

2. Ignition ON, command the Turbocharger Bypass Solenoid Valve between Inactive and Active with a scan tool. You should hear an audible

click.

3. Engine running, command the Turbocharger Bypass Solenoid Valve between Inactive and Active with a scan tool while observing the

following control circuit status parameters:

* Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status

* Turbocharger Bypass Solenoid Valve Control Circuit Open Test Status

* Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage Test Status

The parameters should alternate between OK and Not Run with each change in command.

4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Q40 turbocharger bypass solenoid valve.

2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and

the ignition voltage circuit fuse is open, test all components connected to the ignition voltage circuit and replace as necessary.

3. Connect a test lamp between the control circuit terminal 2 and the ignition circuit terminal 1.

Note: If any Turbocharger circuit DTC is set, the Bypass Solenoid Valve output control may not function. It may be necessary to clear the

DTCs with a scan tool to enable the output control.

4. Command the Turbocharger Bypass Solenoid Valve between Inactive and Active with a scan tool, then select exit. The test lamp should

illuminate and then go OFF.

瀚慖f the test lamp is always ON, test the control circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K20 ECM.

瀚慖f the test lamp is always OFF, test the control circuit terminal 2 for a short to voltage or an open/high resistance. If the circuit tests

normal, replace the K20 ECM.

5. Test for 2.6-4.6 V between the control circuit terminal 2 and ground.

瀚慖f the voltage is not within the specified range, replace the K20 ECM.

6. If all circuits test normal, test or replace the Q40 turbocharger bypass solenoid valve.

Component Testing

1. Ignition OFF, disconnect the harness connector at the Q40 turbocharger bypass solenoid valve.

2. Test for 12-60 ohm between the control terminal 2 and the ignition terminal 1 of the Q40 turbocharger bypass solenoid valve.

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 155

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 155

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

1. Verify that DTC B048D 01 or B048D 06 is not set.

瀚慖f DTC is present, refer to Electrical Auxiliary Heater Control Circuit Malfunction.

2. Verify that DTC B048E 00 is not set.

瀚慖f DTC is present, refer to Electrical Auxiliary Heater Signal Circuit Malfunction.

Circuit/System Testing

Electrical Auxiliary Heater Control Circuit Malfunction

1. Ignition OFF, disconnect the X2 harness connector at the K33 HVAC Control Module and the X1 harness connector at the E40 Electrical

Auxiliary Heater.

2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 2 X1 and ground.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

3. Test for less than 0.3 V between the control circuit terminal 7 X2 at the K33 HVAC Control Module harness connector and ground.

瀚慖f greater than the specified range, test the control circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the control circuit terminal 7 X2 at the K33 HVAC Control Module harness connector and

ground.

瀚慖f less than the specified value, test the control circuit for a short to ground.

5. Test for less than 5 ohm between the K33 HVAC Control Module control circuit terminal 7 X2 and control circuit terminal 1 X1 at the E40

Electrical Auxiliary Heater harness connector.

瀚慖f greater than the specified value, test the control circuit for an open/high resistance.

6. If all circuits test normal, replace the E40 Electrical Auxiliary Heater and verify the DTC does not reset.

Electrical Auxiliary Heater Signal Circuit Malfunction

1. Ignition OFF, disconnect the X2 harness connector at the K33 HVAC Control Module and the harness connectors at the E40 Electrical

Auxiliary Heater.

2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 X2 at the E40 Electrical Auxiliary Heater harness connector

and ground.

瀚慖f the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Verify that a test lamp illuminates between the B+ circuit terminal 1 X2 and ground circuit terminal 1 X3.

瀚慖f the test lamp does not illuminate, test the ground circuit for an open/high resistance.

4. Verify that a test lamp illuminates between the ignition circuit terminal 2 X1 and ground circuit terminal 1 X3.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

5. Test for less than 0.3 V between the signal circuit terminal 5 X2 at the K33 HVAC Control Module harness connector and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage.

6. Ignition OFF, test for infinite resistance between the signal circuit terminal 5 X2 at the K33 HVAC Control Module harness connector and

ground.

瀚慖f less than the specified value, test the signal circuit for a short to ground.