Volt

DTC B3120

The passenger front door handle aerial is located in the passenger front door handle assembly and is used to establish low frequency communications with the keyless entry transmitter. As a vehicle with locked doors is approached with a keyless entry transmitter and the exterior door handle is pulled, the keyless entry control module communicates with the passenger front door handle keyless entry aerial.

B3120 02

The keyless entry control module detects a short to ground on the passenger front door keyless entry aerial signal circuit.

B3120 05

The keyless entry control module detects a short to B+ or an open on the passenger front door keyless entry aerial signal circuit.

Doors will not unlock when front passenger handle is pulled. Doors will not lock with passenger touch pad.

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 B3122, B3123, or B3124 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. Refer to Circuit/System Testing.

Note: The A24P passenger exterior door handle assembly has two harness connectors. Of these two harness connectors, make sure that only the T10N passenger 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 T10N passenger door handle 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 pulling the driver exterior door handle.
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 pulling the driver exterior door handle.
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 1 V

10. Replace the A24D driver exterior door handle assembly.
11. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by pulling the driver exterior door handle.
12. Verify DTC B3120 is not set as current.

⇒	If DTC B3120 is set as current

Replace the K84 keyless entry control module.

⇓	If DTC B3120 is not set or is set as history

13. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.