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DTC B3123

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.

DTC Descriptors

DTC B3123 02: Keyless Entry Aerial 5 Short to Ground

DTC B3123 05: Keyless Entry Aerial 5 High Voltage/Open

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Keyless Entry Aerial Signal - Centre Console Rear

B3123 02

B3123 05

B3123 05

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Keyless Entry Aerial Low Reference - Centre Console Rear

-

B3123 05

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Circuit/System Description

The rear centre console aerial is located in rear of the centre 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, the keyless entry control module communicates with the rear centre console aerial.

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.
    • The last door becomes closed.
    • Pressing the start/stop switch.

Conditions for Setting the DTC

B3123 02

The keyless entry control module detects a short to ground on the rear centre console keyless entry aerial signal circuit.

B3123 05

The keyless entry control module detects a short to B+ or an open on the rear centre console keyless entry aerial signal circuit.

Action Taken When the DTC Sets

Vehicle will not detect the transmitter in some locations inside the vehicle. If the transmitter is not detected then vehicle will not change ignition modes when start/stop button 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 40 malfunction-free ignition cycles.

Reference Information

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

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the T10K centre console rear keyless entry aerial, ignition ON.
  2. Test for less than 1 V between the signal circuit terminal 1 and ground.
  3. If 1 V or greater
    2.1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module, ignition ON.
    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.

  4. 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. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by pressing the ignition mode switch.
  6. Verify the MAX voltage captured by the DMM is greater than 1 V.
  7. If 1 V or less
    5.1. Ignition 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
  8. Test for less than 1 V between the low reference circuit terminal 2 and ground.
  9. If 1 V or greater
    6.1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module, ignition ON.
    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.

  10. 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.
  11. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by pressing the ignition mode switch.
  12. Verify the MAX voltage captured by the DMM is greater than 1 V.
  13. If 1 V or less
    9.1. Ignition 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
  14. Replace the T10K centre console rear keyless entry aerial.
  15. Lock the vehicle doors using the keyless entry transmitter. Activate the aerial by pressing the ignition mode switch.
  16. Verify DTC B3123 is not set as current.
  17. If DTC B3123 is set as current
        Replace the K84 keyless entry control module.
    ⇓   If DTC B3123 is not set or is set as history
  18. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Ignition Lock Key Transmitter Aerial Replacement - Floor Console : Rear → Front
    • Control Module References for keyless entry control module replacement, setup, and programming
   


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