2010 Cadillac Truck SRX FWD V6-3.0L Page 1570

2010 Cadillac Truck SRX FWD V6-3.0L Page 1570

Circuit/System Verification

Engine ON, while rotating the steering wheel to both steering stops, observe the scan tool Cruise Control Switch parameter while pressing each of

the cruise control switches. The parameter should toggle between On, Off, Resume, Set, and Cancel as the applicable switch is pressed.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the S70L steering wheel control switch-left.

2. Ignition ON, test for B+ between the B+ circuit terminal 1 and ground.

瀚慖f less than the specified value, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9

BCM.

3. Test for B+ between the B+ circuit terminal 1 and the signal circuit terminal 2.

瀚慖f less than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace

the K9 BCM.

4. Ignition OFF, disconnect the X1 harness connector at the K9 BCM.

5. Test for infinite resistance between the signal circuit terminal 3 and ground.

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

6. If all circuits test normal, test or replace the S70L steering wheel control switch-left.

Repair Instructions

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

* Cruise Control Switch Replacement (See: Cruise Control/Cruise Control Switch/Service and Repair)

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

P0572

DTC P0572 or P0573

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 P0572

- Brake Switch Circuit 1 Low Voltage

DTC P0573

- Brake Switch Circuit 1 High Voltage

Diagnostic Fault Information

Circuit/System Description

The stop lamp switch signal circuit is a B+ input from the body control module (BCM) to the engine control module (ECM). The ECM monitors

the stop lamp switch circuit to detect when the brake pedal has been applied. The BCM monitors the brake pedal position sensor to determine when

the brake pedal is applied. When the brake pedal is applied, the BCM supplies B+ on the stop lamp switch signal circuit and also sends a serial data

message to the ECM indicating that the brake pedal has been applied.

Conditions for Running the DTC

* The engine is running.