Remote Vehicle Start Malfunction

Remote Vehicle Start Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of each diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

Circuit/System Description

Remote vehicle start begins as an radio frequency message received by the BCM (BCM) from a keyless entry transmitter. The BCM monitors system conditions such as content theft deterrent, hood ajar status, and body DTCs to determine if a remote vehicle start event will occur. If conditions are determined to be acceptable, the remote vehicle start message is sent to the engine control module (ECM). The ECM monitors system conditions such as engine control parameters and vehicle theft deterrent to determine if engine starting will be allowed. If conditions are acceptable, the ECM will initiate engine starting. During the engine run time in a remote vehicle start attempt, before the operator enters the vehicle, the ECM may discontinue engine operation if system conditions require it or a message is received from the BCM requesting the engine be turned OFF.

Diagnostic Aids

Note: If the vehicle has a current vehicle DTC that illuminates the malfunction indicator lamp (MIL), the cause of the DTC must be diagnosed before proceeding with the Remote Vehicle Start Inoperative diagnostic.

The remote vehicle start system will not operate if any of the following conditions are present:

* A current vehicle DTC that illuminates the malfunction indicator lamp (MIL)
* The vehicle is in valet mode.
* More than 2 remote starts have been attempted.
* The hazard switch is in the ON position.
* A current hazard switch DTC is set.
* The vehicle hood is ajar.
* A current hood ajar DTC is set.
* The content theft deterrent system detects an alarm trigger.
* Excessive engine RPM
* Excessive coolant temperature
* Accelerator pedal position greater than 0 percent
* Vehicle not in park
* Vehicle theft deterrent malfunction
* A current automatic transmission shift lock control system DTC is set.
* A vehicle speed sensor signal is detected by the ECM.

Reference Information
Schematic Reference

Remote Function Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Keyless Entry System Description and Operation (without ATH) (Keyless Entry System Description and Operation (Without ATH))Keyless Entry System Description and Operation (with ATH) (Keyless Entry System Description and Operation (With ATH))
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Verify that remote vehicle start is enabled through vehicle personalization.

• If remote vehicle start is not enabled, use vehicle personalization to turn on remote vehicle start functionality. Refer to the vehicle owners manual.

2. Verify that the keyless entry functions operate with all available keyless entry transmitters.

• If the keyless entry system does not function properly, refer to Keyless Entry System Malfunction (with ATH) (Keyless Entry System Malfunction (With ATH))Keyless Entry System Malfunction (without ATH) (Keyless Entry System Malfunction (Without ATH)).

3. Observe the scan tool BCM Remote Start Diagnostic Status History and the ECM Remote Vehicle Start Disable History parameters. Verify that no Diagnostic Status History or Start Disable items are present.

• If remote vehicle start disable history items are present, refer to the appropriate subsection in which the failure occurred.

4. Verify the scan tool BCM Content Theft Trigger History parameters displays None.

• If not specified value, refer to Content Theft Deterrent Malfunction (Content Theft Deterrent Malfunction).