• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Cruise Control Switch Signal | 1 | 1 | P0567 or P0568 | P0564 |
1. Cruise Control Inoperative / Malfunctioning |
The cruise control switch is an input to the engine control module (ECM), while the cruise cancel switch is an input to the body control module (BCM). The ECM monitors the cruise control on/off, set/coast, and the resume/accelerate switch signal circuits in order to detect when a cruise control function switch has been activated. The ECM detects a predetermined voltage signal when a cruise control function switch is applied, with each switch having a different voltage value.
The BCM monitors the cruise cancel switch in order to detect when the cancel switch has been activated. The BCM sends a class 2 message to the ECM regarding the status of the cruise cancel switch.
• | The cruise switch is ON. |
• | The ignition is ON. |
• | The ECM detects an invalid voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit. |
• | The above condition is present for greater than 1.5 seconds. |
• | The PCM/ECM runs this diagnostic every 0.05 second. |
• | The ECM stores the DTC information into memory when the diagnostic runs and fails. |
• | The malfunction indicator lamp (MIL) will not illuminate. |
• | The Cruise Control System is disabled. |
• | The DTC becomes history when the fault is no longer present. |
• | A History DTC clears after 100 malfunction-free ignition cycles. |
• | The ECM receives a clear code command from the scan tool. |
With the engine ON and with a scan tool, observe the cruise control function switch parameters, in the Cruise Control ECM data list, while rotating the steering wheel to both steering stops and individually activating each cruise control function switch separately. This will help eliminate the possibility of an internally shorted inflatable restraint steering wheel module coil.
Cruise Control Description and Operation
⇒ | If less than the specified value, test the cruise control supply voltage circuit for an open/high resistance or a short to ground. |
⇒ | If the test lamp does not illuminate, test the cruise control switch signal circuit for an open/high resistance or a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If the test lamp illuminates, test the cruise control switch signal circuit for a short to ground. |
Important: The cruise control switch must be ON in order to properly measure the resistance of the - SET, the + RES, and the Cancel switches.
⇒ | If any of the resistance measurements for the OFF, ON, - SET, and + RES are not within the listed resistance values, replace the cruise control switch assembly. |
⇒ | If the resistance does not show continuity when activated and open when deactivated, replace the cruise control switch assembly. |
Function Switch | Minimum Resistance Value | Maximum Resistance Value |
---|---|---|
OFF | O.L. | O.L. |
ON | 7.9k Ohms | 8.6k Ohms |
- SET | 1.3k Ohms | 1.7k Ohms |
+ RES | 4.2k Ohms | 4.6k Ohms |
Cancel | 0.0k Ohms | 0.5k Ohms |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |