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B3122




DTC B3122

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptors
DTC B3122 02
- Keyless Entry Antenna 4 Short to Ground

DTC B3122 05
- Keyless Entry Antenna 4 High Voltage/Open

Diagnostic Fault Information





Circuit/System Description

The front center console antenna is located in front of the center console assembly and is used to establish low frequency communications with the keyless entry transmitter. When the driver attempts to change the ignition status of the vehicle, i.e. starting the vehicle, the keyless entry control module communicates with the front center console antenna.

Conditions for Running the DTC

* The touch pad in the driver door or passenger door handle is touched within 15 minutes of any door ajar status changing.
* Any exterior door handle or handles is pulled.
* The last door becomes closed.
* Pressing the start/stop switch.
* The scan tool activates a device control function to simulate the above actions.

Conditions for Setting the DTC

B3122 02

The keyless entry control module detects a short to ground on the front center console keyless entry antenna circuit.

B3122 05

The keyless entry control module detects a short to B+ or an open on the front center console keyless entry antenna circuit.

Action Taken When the DTC Sets

* Vehicle will not detect the key fob in some locations inside the vehicle. If key fob is not detected then vehicle will not start when start/stop button is pressed.
* Doors will not unlock when any door handle is pulled. Doors will not lock with touch pad. Rear closure will not open when doors are locked and touch pad is pressed.

Conditions for Clearing the DTC

* A current DTC will clear when the conditions for setting the DTC are no longer present.
* A history DTC will clear after 50 malfunction-free ignition cycles.

Reference Information
Schematic Reference

Remote Function Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Keyless Entry System Description and Operation (without ATH) (Keyless Entry System Description and Operation (Without ATH))Keyless Entry System Description and Operation (with ATH) (Keyless Entry System Description and Operation (With ATH))
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

Note: Verify that the pins are correct for all of the antennas. If DTC B3122 is set, any problems with B3123 has to be fixed first before proceeding to fix the problem with B3122.

1. Ignition OFF, disconnect the harness connector at the T10J front center console antenna.
2. Ignition ON, verify a test lamp does not illuminate between the signal circuit terminal 1, connector on vehicle side, and vehicle ground and also does not illuminate between low reference signal circuit terminal 2, connector on vehicle side, and vehicle ground.

If the test lamp illuminates, disconnect the connector at the keyless entry control module, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the keyless entry control module.

3. Connect a DMM, set to capture DC voltage using the MIN MAX function, between the signal circuit terminal 1 and vehicle ground.

Note: Use DC voltage because comparing to vehicle ground

4. Activate the front center console antenna by pressing the start/stop button or pulling any exterior door handle or handles. After hitting the min/max button looking for any voltage, verify the DMM captured a DC voltage signal.

If the DC voltage was not captured, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the keyless entry control module.

5. Connect a DMM, set to capture DC voltage using the MIN MAX function, between the low reference circuit terminal 2 and vehicle ground.
6. Activate the front center console antenna by pressing the start/stop button or pulling any exterior door handle or handles. After hitting the min/max button looking for any voltage, verify the DMM captured a DC voltage signal.

If the DC voltage was not captured, test the low reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the keyless entry control module.
Clear DTCs then activate the front center console antenna by pressing the start/stop button or pulling any exterior door handle or handles and check for DTCs again.
If DTC B3122 returns replace the T10J front center console antenna. Clear DTCs again then activate the front center console antenna by pressing the start/stop button or pulling any exterior door handle or handles and check for DTCs.
If DTC B3122 returns, replace the keyless entry control module.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for keyless entry control module replacement, setup, and programming