Volt

Keyless Entry System Malfunction - Passive

The keyless entry aerials 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 aerial broadcasts a challenge to the transmitter in an approximate 1 metre 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.

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

Scan Tool Reference

Control Module References for scan tool information

1. Vehicle in Service Mode.
2. Verify that DTC B3119, B3120, or B3121 is not set.

⇒	If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

⇓	If none of the DTCs are set

3. Verify that the transmitter is a correct transmitter for the vehicle. This can be accomplished by comparing the part number printed on the transmitter to the appropriate part number in the parts catalogue.

⇒	If the transmitter is incorrect

Replace the transmitter.

⇓	If the transmitter is correct

4. Verify the scan tool Exterior Driver Door Handle Switch, Exterior Passenger Door Handle Switch, and Boot Lid Exterior Unlatch Switch parameters change between Active and Inactive while operating their respective release handle/touch pad.

⇒	If any of the parameters does change

Refer to Exterior Door Handle Switch Malfunction - DTC B1474, B1534, B1535, or B3849 .

⇓	If all of the parameters change

5. Lock the vehicle using the keyless entry transmitter.
6. Verify that each door and rear compartment unlocks and opens by approaching the vehicle with a valid transmitter and operating their respective release handle/touch pad.

⇒	If both doors and the rear compartment do not unlock/unlatch and open

Refer to Passive Transmitter Malfunction.

⇒	If only one door or the rear compartment does not unlock/unlatch and open

Refer to Aerial Circuit Malfunction.

⇓	If both doors and the rear compartment unlocks/unlatches and opens

7. All OK.

Passive Transmitter Malfunction

1. Lock the vehicle using the keyless entry transmitter.
2. Verify that each door and rear compartment unlocks and opens by approaching the vehicle with a valid transmitter and operating their respective release handle/touch pad.

⇒	If both doors and the rear compartment do not unlock/unlatch and open

2.1.	Replace the transmitter battery.

2.2.	Lock the vehicle using the keyless entry transmitter.

2.3.	Verify that each door and rear compartment unlocks and opens by approaching the vehicle with a valid transmitter and operating their respective release handle/touch pad.

⇒	If both doors and the rear compartment do not unlock/unlatch and open, replace the transmitter.

⇓	If both doors and the rear compartment unlock/unlatch and open

2.4.

All OK.

⇓	If both doors and the rear compartment unlock/unlatch and open

3. The concern may be caused by temporary RF interference. Discuss the conditions in which the concern occurs with the customer. RF interference from aftermarket devices such as 2-way radios, power inverters, mobile 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.

Aerial Circuit Malfunction

Note: The A24 exterior door handle assembly has two harness connectors. Of these two harness connectors, make sure that only the T10 door handle keyless entry aerial harness connector is disconnected. Disconnecting both harness connectors will result in the inability to activate the aerial and cause an improper diagnosis.

1. Vehicle OFF, disconnect the harness connector at the inoperative T10 keyless entry aerial, Vehicle in Service Mode.
2. Test for less than 1 V between the signal circuit terminal 1 and ground.

⇒	If 1 V or greater

2.1.	Vehicle OFF, disconnect the harness connector at the K84 keyless entry control module, Vehicle in Service Mode.

2.2.	Test for less than 1 V between the signal circuit and ground.

⇒	If 1 V or greater, repair the short to voltage on the circuit.

⇒	If less than 1 V, replace the K84 keyless entry control module.

⇓	If less than 1 V

Note: When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.

3. Vehicle OFF, install a DMM between the signal circuit terminal 1 and ground. Set the DMM to capture DC voltage using the MIN MAX function.
4. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by operating the appropriate release handle/touch pad.
5. Verify the MAX voltage captured by the DMM is greater than 1 V.

⇒	If 1 V or less

5.1.	Vehicle OFF, disconnect the harness connector at the K84 keyless entry control module.

5.2.	Test for infinite resistance between the signal circuit and ground.

⇒	If less than infinite resistance, repair the short to ground on the circuit.

⇓	If infinite resistance

5.3.	Test for less than 2 Ω in the signal circuit end to end.

⇒	If 2 Ω or greater, repair the open/high resistance in the circuit.

⇒	If less than 2 Ω, replace the K84 keyless entry control module.

⇓	If greater than 1 V

6. Test for less than 1 V between the low reference circuit terminal 2 and ground.

⇒	If 1 V or greater

6.1.	Vehicle OFF, disconnect the harness connector at the K84 keyless entry control module, Vehicle in Service Mode.

6.2.	Test for less than 1 V between the low reference circuit and ground.

⇒	If 1 V or greater, repair the short to voltage on the circuit.

⇒	If less than 1 V, replace the K84 keyless entry control module.

⇓	If less than 1 V

Note: When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.

7. 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.
8. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by operating the appropriate release handle/touch pad.
9. Verify the MAX voltage captured by the DMM is greater than 1 V.

⇒	If 1 V or less

9.1.	Vehicle OFF, disconnect the harness connector at the K84 keyless entry control module.

9.2.	Test for less than 2 Ω in the low reference circuit end to end.

⇒	If 2 Ω or greater, repair the open/high resistance in the circuit.

⇒	If less than 2 Ω, replace the K84 keyless entry control module.

⇓	If greater than 1V

10. Replace the appropriate T10 keyless entry aerial.
11. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by operating the appropriate release handle/touch pad.
12. Verify that the door/rear compartment unlocks and opens when the release handle/touch pad is operated.

⇒	If the door/rear compartment does not unlock and open

Replace the K84 keyless entry control module.

⇓	If the door/rear compartment unlocks and opens

13. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.