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, B3794 61 |
Cruise Control Switch Signal | 1 | B3794 08 | 1 | B3794 08 | B3794 08, B3794 61 |
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 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.
Conditions for Enabling Cruise Control
| • | The vehicle speed is greater than 40 km/h (25 mph). |
| • | The vehicle is not in PARK, REVERSE, NEUTRAL, or 1st gear. |
| • | The system voltage is within 9-16 volts. |
| • | The park brake is not applied. |
| • | The brake pedal is not applied. |
| • | The scan tool brake pedal position sensor parameter indicates released. |
| • | The scan tool brake pressure sensor voltage parameter is within the correct range. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Cruise Control Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
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
- Ignition OFF, disconnect the harness connector at the steering wheel controls switch - left.
- Ignition ON, test for B+ between the B+ circuit terminal 1 and ground.
- Test for B+ between the B+ circuit terminal 1 and the signal circuit terminal 3.
- Ignition OFF, disconnect the X1 harness connector at the BCM.
- Test for infinite resistance between the signal circuit terminal 3 and ground.
- If all circuits test normal, test or replace the steering wheel control switch-left.
| ⇒ | If less than the specified value, test the voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
| ⇒ | 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. |
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. |
Component Testing
- Disconnect the harness connector at the steering wheel controls switch - left.
- Cruise control switch ON, measure the resistance between terminal 1 and terminal 3 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, steering wheel controls switch - left. |
Function Switch | Minimum Resistance Value | Maximum Resistance Value |
|---|---|---|
OFF | O.L. | O.L. |
ON | 6.6K Ohms | 7.0K Ohms |
-/SET | 2.1K Ohms | 2.5K Ohms |
+/RES | 3.6K Ohms | 4.0K Ohms |
Cancel | 1.3K Ohms | 1.7K Ohms |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
