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B3120



DTC B3120

Circuit Description

The keyless entry antenna - right is located in the right hand B-pillar area and is used as a short range low frequency (LF) transmitter. As a vehicle with locked doors is approached with a key fob, and the exterior door handle switch is pressed, the keyless entry antenna transmitter broadcasts a challenge to the key fob in approximately a 1 meter range. If the response from the key fob via radio frequency (RF) is valid, then the locked door will be passively unlocked/unlatched and allow the door to be opened.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3120 Keyless Entry Antenna 2 Performance

Conditions for Setting the DTC

The remote control door lock receiver (RCDLR) will set this DTC during antenna activation if the keyless entry antenna - right is open, shorted to battery or shorted to ground and an authentication occurs. 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 B3120.

Conditions for Clearing the DTC

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

Test Description

Step 1 - Step 10:




Step 11:




The numbers below refer to the step numbers on the diagnostic table.
2. Verifies that DTC B3120 is a current DTC.
3. Testing for power and ground to the keyless entry antenna.