Keyless Entry System Malfunction

Keyless Entry System 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 the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The keyless entry system is a vehicle entry device. The keyless entry will unlock the vehicle doors or open the rear compartment when a corresponding button on the keyless entry transmitter is pressed. This is accomplished by the keyless entry transmitter sending a radio frequency to the remote control door lock receiver (RCDLR). The RCDLR interprets the signal and activates the requested function via a message over the GMLAN serial data line. A low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. may cause a system malfunction. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction.

Diagnostic Aids

Unwanted or inadvertent door lock/unlock activation may actually be triggered by the OnStar(R) Remote Link Apps. Customer may be unaware of account usage, contact Technical Assistance Center (TAC) if root cause cannot be diagnosed to vehicle.

For the J 43241 - keyless entry tester, inspect the keyless entry transmitter part number to determine that it is the correct model for the vehicle. A wrong model transmitter may pass the test, but it will not activate the vehicle remote system.

Reference Information

Schematic Reference

Remote Function Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views Connector End Views By Name

Description and Operation

Keyless Entry System Description and Operation Description and Operation

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 Control Module References for scan tool information

Special Tools

J 43241 - Keyless Entry Tester

Circuit/System Verification

1. Place the transmitter on the test pad of the J 43241 - keyless entry tester and press each transmitter button one at a time, holding each button for three seconds. The tester should sound a tone and illuminate a green light for the entire three second button press.

• If one or more buttons does not sound the tone and illuminate the green light for the entire three seconds, replace the transmitter battery and retest with the J 43241 - keyless entry tester. If the condition continues after battery replacement, replace the transmitter.

2. Program the transmitter. Refer to Remote Control Door Lock Transmitter Learn Testing and Inspection. The transmitter should successfully complete the programming procedure.

• If the transmitter does not program, replace the keyless entry transmitter. If the new keyless entry transmitter does not complete the programming, replace the RCDLR.

3. Operate the transmitter function while observing the vehicle. The vehicle should perform each of the corresponding functions when selected on the transmitter.

• If any of the vehicle functions are inoperative, replace the keyless entry transmitter. If the functions remain inoperative after replacement of the transmitter, replace the RCDLR.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Remote Control Door Lock Transmitter Learn Testing and Inspection

* Control Module References Control Module References for RCDLR replacement, programming and setup