For 1990-2009 cars

### 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.

### Circuit/System Description

The keyless entry system is a vehicle entry device. Keyless entry will unlock the vehicle doors when a corresponding button on the remote-key is pressed. This is accomplished by the remote-key sending a radio frequency to the steering column module (CIM). The CIM interprets the signal and activates the requested function. A low remote-key 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.

### Reference Information

#### Schematic Reference

Remote Function Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Keyless Entry System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

#### Special Tools Required

J 43241 Keyless Entry Tester

### Circuit/System Verification

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

⇒ | If one or more buttons does not sound the tone and illuminate the green light, replace the remote-key battery and retest with the J 43241 . If the condition continues after battery replacement, replace the remote-key.

2. Verify the scan tool Transponder Key parameter for the appropriate remote-key is Programmed.

⇒ | If not the specified value, program the remote-key. Refer to Replacing Keys.

3. Operate the remote-key while observing the scan tool Remote Key Function parameters. The parameter should correspond with the function selected on the remote-key.

⇒ | If the parameter does not match the function selected on the remote-key, program the remote-key and retest. Refer to Replacing Keys. If the condition continues after remote-key programming, replace the remote-key.

4. If all circuits test normal, replace the CIM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Replacing Keys

• | Control Module References for CIM replacement, setup, and programming