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 garage door opener (GDO) is a transmitter operating between 288 and 399 MHz. The GDO has 3 buttons that may be programmed for individual transmitter/receiver combinations to control up to 3 GDOs, security gates, and lighting systems. Each button represents a transmitter code section of the transmitter, which operates separately from any other button, and may be considered a separate transmitter.

### Diagnostic Aids

GDO operation is dependent on the position of the valet switch, if equipped. If the vehicle is equipped with a valet switch, verify it is not in valet mode before continuing with the diagnostics.

### Reference Information

#### Schematic Reference

Remote Function Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Garage Door Opener 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

J 41540 Universal Home Remote Tester

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the GDO.
2. Ignition OFF, test for less than 1 ohm of resistance between the ground circuit terminal 3 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4. Hold the 2 outer buttons on the GDO until the LED stops flashing. Place the J 41540 adjacent to the GDO and individually press each button of the GDO. The tester should indicate when each button is pressed.

⇒ | If one or more of the buttons does not respond when each button is pressed, replace the GDO.

5. Program the GDO with the customer's device. The GDO should learn the device.

⇒ | If the device is not learned, a possible rolling code or incompatibility with the GDO receiver will prevent programming. Contact 1-800-355-3515.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for GDO replacement, setup, and programming