Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The keyless entry system is a vehicle entry device. The keyless entry will lock/unlock the vehicle doors or open the rear compartment when a corresponding button on the key fob is pressed. This is accomplished by the key fob sending a radio frequency to the remote control door lock receiver (RCDLR). The signal is received by the RCDLR via an internal antenna located within the RCDLR. The RCDLR interprets the signal and activates the requested function via a message over the 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.

For the J 43241 , 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.

Schematic Reference

Keyless Entry Schematics

Connector End View Reference

Keyless Entry Connector End Views

Description and Operation

Keyless Entry System Description and Operation

Electrical Information Reference

Scan Tool Reference

1. Verify that the transmitter is the correct transmitter for the vehicle.

⇒	If not the correct transmitter, replace the transmitter.

2. Place the transmitter on the test pad of the J 43241 and press each button of the transmitter one at a time. The tester should sound a tone and illuminate a green light when each button is pressed.

⇒	If none of the buttons sounds the tone and illuminates the green light, replace the battery.

⇒	If one or more of the buttons sounds the tone and illuminates the green light, replace the transmitter.

3. Press each transmitter button one at a time. Verify the scan tool Last RFA Command Received parameter responds to each function.

⇒	If the parameter does not respond to every function, replace the RCDLR.

4. Replace the transmitter.

Control Module References for BCM or RCDLR replacement, setup, and programming