For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
B+ | 1 | B3794 08 | 1 | 1 | B3794 08
Cruise Control Switch Signal | 1 | B3794 08 | 1 | B3794 08 | B3794 08
Ground | -- | 1 | 1 | -- | --
1. Cruise Control Malfunction

### Circuit/System Description

The cruise control switch is an input to the body control module (BCM). The BCM monitors the cruise control on/off, set/coast, resume/accelerate and cancel switches via the cruise control switch signal circuit in order to detect when the driver has requested to perform a cruise control function. The BCM detects a specific voltage signal on the cruise control switch signal circuit when a switch is applied. The BCM sends a serial data message to the engine control module (ECM) indicating the status of the cruise control switches.

### Reference Information

#### Schematic Reference

Cruise Control Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Cruise Control Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the steering wheel controls switch - left.
2. Ignition OFF, test for less than 10 ohms between the ground circuit terminal 7 and ground.

⇒ | If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition ON, test for B+ between the B+ circuit terminal 4 and ground.

⇒ | If less than the specified value, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Ignition ON, test for B+ between the circuit terminal 4 and the signal circuit terminal 5.

⇒ | If 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 BCM.

5. Ignition OFF, disconnect the X2 harness connector at the BCM.
6. Test for infinite resistance between the signal circuit terminal 61 and ground.

⇒ | If less than the specified value, test the signal circuit for a short to ground.

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

### Component Testing

1. Disconnect the harness connector at the steering wheel control switch-left.
2. Cruise control switch ON, measure the resistance between terminal 4 and terminal 5 while individually activation and holding each cruise control function switch and compare the resistance reading to the values in the table below.

⇒ | If not within the specified resistance range, replace the steering wheel control switch-left.

Function Switch | Minimum Resistance Value | Maximum Resistance Value
--- | --- | ---
Off | O.L. | O.L.
On | 8.1k Ohms | 8.4k Ohms
- SET | 1.2k Ohms | 1.4k Ohms
+ RES | 2.8k Ohms | 3.0k Ohms

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Steering Wheel Control Switch Assembly Replacement

• | Control Module References for BCM replacement, setup, and programming