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 Antenna 5 & 6 Performance Short to GroundDTC B3123 04: Keyless Entry Antenna 5 & 6 Performance Open
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Keyless Entry Antenna - Signal (4) | B3119 02 | B3119 05 | B3119 05 | -- |
Keyless Entry Antenna - Low Reference (4) | -- | B3119 05 | -- | -- |
Keyless Entry Antenna - Signal (5) | B3120 02 | B3120 05 | B3120 05 | -- |
Keyless Entry Antenna - Low Reference (5) | -- | B3120 05 | -- | -- |
Keyless Entry Antenna - Signal (3) | B3121 02 | B3121 05 | B3121 05 | -- |
Keyless Entry Antenna - Low Reference (3) | -- | B3121 05 | -- | -- |
Keyless Entry Antenna - Signal (2) | B3123 02 | B3123 04 | B3123 04 | -- |
Keyless Entry Antenna - Low Reference (2) | -- | B3123 04 | -- | -- |
Keyless Entry Antenna - Signal (1) | B3123 02 | B3123 04 | B3123 04 | -- |
Keyless Entry Antenna - Low Reference (1) | -- | B3123 04 | -- | -- |
Keyless Entry Active Antenna Supply Voltage | B3122 04 | B3122 04 | B3122 04 | -- |
Keyless Entry Active Antenna Data Signal | B3122 04 | B3122 04 | B3122 04 | -- |
Keyless Entry Active Antenna Clock Signal | B3122 04 | B3122 04 | B3122 04 | -- |
Keyless Entry Active Antenna Low Reference | -- | B3122 04 | -- | -- |
Circuit/System Description
The headliner and console passive antennas are located in the rear headliner area and in the center console. They are used as short range low frequency (LF) antennas. The headliner and console antennas are used to determine transmitter placement within the vehicle. When a valid keyless entry transmitter is within the passenger compartment, the headliner and console antennas broadcast a challenge within the passenger compartment to the transmitter. If the response from the transmitter via radio frequency (RF) is a valid response, the antenna will determine there is a fob within the vehicle. If no response is received, the antenna determines that no fob is in the vehicle.
The headliner and console passive antennas share a driver within the remote control door lock receiver (RCDLR) and are wired in parallel. The RCDLR has no way to determine which antenna is receiving a valid response from a transmitter, only that a valid response is being received.
Conditions for Running the DTC
A transmitter validation is requested.
Conditions for Setting the DTC
An improper voltage level is seen on the keyless entry antenna - signal (1) or signal (2) circuit.
Action Taken When the DTC Sets
The headline and console passive keyless entry antennas are ignored. Vehicle starting will require the fob to be placed in the console pocket.
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
Connector End View Reference
Description and Operation
Keyless Entry System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the console passive antenna.
- Place the key fob near the headliner antenna and attempt to start the vehicle. The vehicle should start.
- Refer to Console Passive Antenna Circuit Malfunction.
| ⇒ | If the vehicle does not start, refer to Headliner Antenna Circuit Malfunction. |
Headliner Antenna Circuit Malfunction
- Ignition OFF, disconnect the harness connector at the headliner antenna.
- Install a DMM between the signal circuit terminal A and the low reference circuit terminal B. Set the DMM to capture AC voltage using the MIN MAX function.
- Attempt to start the vehicle. Verify the DMM captured an AC voltage signal.
- If all circuits test normal, test or replace the headliner antenna.
| ⇒ | If an AC voltage was not captured, test the signal circuit and the low reference circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the RCDLR. |
Console Passive Antenna Circuit Malfunction
- Install a DMM between the signal circuit terminal A and the low reference circuit terminal B. Set the DMM to capture AC voltage using the MIN MAX function.
- Attempt to start the vehicle. Verify the DMM captured an AC voltage signal.
- If all circuits test normal, test or replace the console passive antenna.
| ⇒ | If an AC voltage was not captured, test the signal circuit and the low reference circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the RCDLR. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for RCDLR replacement, setup, and programming |
