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 | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+ | 1 | B3623 00 | -- | B3623 00 |
Adaptive Cruise Control Switch Signal | 1 | B3623 00 | 1 | B3623 00 |
1. Cruise Control Malfunction | ||||
Circuit/System Description
The body control module (BCM) monitors the adaptive cruise control (ACC) gap adjustment switch signal circuit to determine the driver selected headway. The gap switch is a momentary contact switch that connects a series of resistors. Each switch state, inactive, up and down, corresponds to a specific resistance value. The BCM determines the switch selection by the voltage drop across the resistor.
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
Ignition ON, verify that the ACC Gap Switch parameter toggles accordingly between Up, Down and Inactive as the appropriate gap 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 2.
- Ignition OFF, disconnect the X2 harness connector at the BCM.
- Test for infinite resistance between the signal circuit terminal 57 and ground.
- If all circuits test normal, test or replace the steering wheel controls switch - left.
| ⇒ | If 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 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 2 while individually activating and holding each ACC gap 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 controls switch - left. |
Function Switch | Minimum Resistance Value | Maximum Resistance Value |
|---|---|---|
Neutral | O.L. | O.L. |
Cancel | 1.9k Ohms | 2.1k Ohms |
Gap Up | 3.5k Ohms | 3.7k Ohms |
Gap Down | 6.6k Ohms | 6.8k Ohms |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
