Keyless Entry System Malfunction (Passive)

Keyless Entry System Malfunction (Passive)

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 antennas are used as short range low frequency transmitters. As a vehicle with locked doors is approached with a keyless entry transmitter and the exterior door handle is pulled, the keyless entry antenna broadcasts a challenge to the transmitter in an approximate 1 meter range. If the response from the transmitter via radio frequency (RF) is valid, the locked door will be passively unlocked/unlatched and allow the door to be opened. The front doors will open with one pull of the front door handle. 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.

Reference Information

Schematic Reference

Remote Function Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Keyless Entry System Description and Operation (without ATH) Keyless Entry System Description and Operation (with ATH)

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 43241 Keyless Enter Tester

Circuit/System Verification

1. Verify DTC B3119, B3120, or B3121 is not set.
2. If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
3. Ignition ON, observe the scan tool Exterior Driver Door Handle Switch, Exterior Passenger Door Handle Switch, and Trunk Lid Exterior Unlatch Switch parameters while operating their respective release handle/touch pad. The parameter should change between Active and Inactive as commanded.
4. If the parameter does not cycle between the specified values, refer to Power Door Locks Malfunction (Dead Lock) Power Door Locks Malfunction (Without Dead Locks).
5. With the vehicle locked, attempt to passively unlock and access the vehicle at the left door, right door, and rear compartment by approaching the vehicle with a valid transmitter and operating their respective release handle/touch pad. Each door and the rear compartment should unlock/unlatch and open.
6. If both doors and the rear compartment do not unlock/unlatch and open, refer to Passive Transmitter Malfunction.
7. If only one door or the rear compartment does not unlock/unlatch and open, refer to Antenna Circuit Malfunction.

Circuit/System Testing

Passive Transmitter Malfunction

Place the keyless entry transmitter on the J 43241 and approach the vehicle. Touch the handle/contact pad. Confirm that a tone is heard from J 43241.

Antenna Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the inoperative T10 handle keyless entry antenna.
2. Ignition ON, test for less than 1 V between the signal circuit terminal 1 and ground.
3. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K84 keyless entry control module.

4. NOTE: When using the MIN MAX function, auto-range may not function on the DMM. To ensure accurate test results, turn off auto-range and manually set the DMM range to 000.0 V.

Ignition OFF, install a DMM between the signal circuit terminal 1 and ground. Set the DMM to capture DC voltage using the MIN MAX function.

5. Activate the antenna by pressing the ignition mode switch. Verify the MAX voltage captured by the DMM is greater than 1.0 V.
6. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K84 keyless entry control module.
7. Test for less than 1 V between the low reference circuit terminal 2 and ground.
8. If greater than the specified range, test the low reference circuit for a short to voltage. If the circuit tests normal, replace the K84 keyless entry control module.

9. NOTE: When using the MIN MAX function, auto-range may not function on the DMM. To ensure accurate test results, turn off auto-range and manually set the DMM range to 000.0 V.

Install a DMM between the signal circuit terminal 1 and the low reference circuit terminal 2. Set the DMM to capture DC voltage using the MIN MAX function.

10. Activate the antenna by pressing the ignition mode switch. Verify the MAX voltage captured by the DMM is greater than 1.0 V.
11. If less than the specified range, test the low reference circuit for an open circuit/high resistance. If the circuit tests normal, replace the K84 keyless entry control module.
12. If all circuits test normal, replace the T10 handle keyless entry antenna.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Front Side Door Outside Handle Bracket Replacement
- Ignition Lock Key Transmitter Antenna Replacement - Rear Bumper Fascia
- Control Module References for keyless entry control module replacement, setup, and programming