2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1815

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1815

Note: Disconnecting the throttle body harness connector causes additional DTCs to set.

2. Ignition OFF, disconnect the harness connector of the Q38 throttle body.

3. Ignition ON, test for 4.0-4.2 V between the TAC motor control 1 circuit terminal B and ground.

瀚慖f voltage is greater than the specified range, test each of the motor control circuits for a short to voltage. If the circuits tests normal,

replace the K20 Engine Control Module.

瀚慖f voltage is less than the specified range, test the motor control 1 circuit for a short to ground or an open/high resistance. If the circuit

tests normal, replace the K20 Engine Control Module.

4. Connect a test lamp between the TAC motor control 2 circuit terminal A and B+. The test lamp should NOT illuminate.

瀚慖f the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control

Module.

5. Test for greater than 3.5 V between TAC motor control 1 circuit terminal B and TAC motor control 2 circuit terminal A.

瀚慖f the voltage is less than the specified value, test the motor control 2 circuit for an open/high resistance. If the circuit tests normal,

replace the K20 Engine Control Module.

6. Ignition OFF, connect the EL 34730-405 - Injector Test Lamp between the TAC motor control 1 circuit terminal B and TAC motor control 2

circuit terminal A of the throttle body harness connector. Observe the injector test lamp while turning the ignition ON for 5 s and then OFF.

Verify the injector test lamp illuminates brightly and then turns OFF.

瀚慖f the injector test lamp does not illuminate, replace the K20 Engine Control Module.

7. If all circuits test normal, replace the Q38 throttle body.

Repair Instructions

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

* Throttle Body Assembly Replacement (LF1) (See: Powertrain Management/Fuel Delivery and Air Induction/Throttle Body/Service and

Repair/Removal and Replacement)Throttle Body Assembly Replacement (LAU) (See: Powertrain Management/Fuel Delivery and Air

Induction/Throttle Body/Service and Repair/Removal and Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement, setup, and

programming

P2102

DTC P0638, P2100-P2103, or P2119 (Without LF1, LFW)

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 P0638

- Throttle Actuator Control (TAC) Command Performance

DTC P2100

- Throttle Actuator Control (TAC) Motor Control Circuit

DTC P2101

- Throttle Actuator Position Performance

DTC P2102

- Throttle Actuator Control (TAC) Motor Control Circuit Low Voltage

DTC P2103

- Throttle Actuator Control (TAC) Motor Control Circuit High Voltage