2010 Cadillac CTS Sedan AWD V6-3.6L Page 1074

2010 Cadillac CTS Sedan AWD V6-3.6L Page 1074

The ECM detects a fault in an ignition coil control circuit for 50 out of 63 samples. Each sample runs on a 6.25 ms loop.

Action Taken When the DTC Sets

DTCs P135A and P135B are Type A DTCs.

Conditions for Clearing the DTC

DTCs P135A and P135B are Type A DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics

(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

* Electronic Ignition System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Electronic Ignition System Description)

* Engine Control Module Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Engine

Control Module Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)

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

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

Engine Control Module Scan Tool Information (V6) (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Scan

Tool Testing and Procedures)Engine Control Module Scan Tool Information (V8) (See: Powertrain Management/Computers and Control

Systems/Testing and Inspection/Scan Tool Testing and Procedures)Engine Control Module Scan Tool Information (LF1) (See: Powertrain

Management/Computers and Control Systems/Testing and Inspection/Scan Tool Testing and Procedures) for scan tool information

Circuit/System Verification

With the ignition ON, observe the following scan tool parameters for each cylinder:

* Ignition Coil Supply Voltage Bank 1

* Ignition Coil Supply Voltage Bank 2

瀚慐ach parameter should display ON.

Circuit/System Testing

Note: The ignition circuit supplies voltage to other components. Make sure you test all circuits for a short to ground or test all components for

being shorted that share the ignition circuit.

1. Ignition OFF, disconnect the harness connector at the appropriate T8 ignition coil.

2. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal D and ground of each T8 ignition coil.

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

瀚慖f the circuit tests normal, with the ignition OFF, disconnect the harness connector at each T8 ignition coil and monitor the fuse while

individually connecting each T8 ignition coil. If the fuse opens, replace the appropriate T8 ignition coil.

3. Ignition OFF, disconnect the K20 ECM harness connector X1.

4. Ignition ON, connect a test lamp between the following ignition voltage circuits and ground:

* X1 67

* X1 62

The test lamp should illuminate on each circuit.