B3123

DTC B3123

Circuit Description

The headliner and console antennas are located in the rear headliner area and in the center console. They are used as a 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 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.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3123 Keyless Entry Antenna 5&6 Performance






Conditions for Setting the DTC

The RCDLR will set this DTC during antenna activation if the headliner and console antenna is open, shorted to battery, or shorted to ground. The RCDLR can only set a DTC when the vehicle system voltage is between 9-16 volts.

Action Taken When the DTC Sets

The RCDLR will set and store a DTC B3123.

Conditions for Clearing the DTC

* The RCDLR no longer detects an open, a short to power, or a short to ground on the antenna circuit.
* The use of a scan tool

Test Description

Step 1 - Step 4:

Step 5 - Step 14:

The numbers below refer to the step numbers on the diagnostic table.
2. This step verifies that DTC B3123 is a current DTC.
3. This step tests the function of the headliner antenna. Because the console antenna and headliner antenna share a drive within the RCDLR, the console antenna must be disconnected to properly check functionality of the headliner antenna.
4. This step verifies the RCDLR is sending out the required AC voltage signal to the headliner antenna.
5. This step verifies the RCDLR is sending out the required AC voltage signal to the console antenna.