B2508

DTC B2508 or B2509

Circuit Description

When the heated seat system is activated, the body control module (BCM) controls the heated seat operation through the heated seat relay control circuit and the heated seat relay. The relay energizes and applies battery positive voltage to the seat heater elements. The circuit that generated this DTC is the heated seat relay control circuit that is wired between the BCM and the heated seat relay.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

* DTC B2508 Seat Heater Relay Circuit
* DTC B2509 Seat Heater Relay Circuit

Conditions for Running the DTC

* The BCM must be powered and cannot have B1327, Battery Voltage Low, as an active DTC for this DTC to set.
* The BCM monitors the voltage of this circuit at all times, even when the ignition is in the OFF position.
* The module voltage must be 9-16 volts.

Conditions for Setting the DTC

* Open detected when the output is inactive.
* Short to battery positive voltage detected when the output is inactive.
* Short to ground detected when the output is inactive
* Open in the ground circuit of the heated seat relay.

Action Taken When the DTC Sets

Current and history DTCs are stored.

Conditions for Clearing the DTC

The BCM will clear the current DTC when the short to ground, battery voltage, or open is no longer present.

Test Description

Step 1 - Step 11:

Step 12 - Step 13:

The numbers below refer to the step numbers on the diagnostic table.
2. During the heated seat relay operation, listen for an audible click from the relay. Repeat the commands, as necessary.
4. This step verifies that the BCM is providing voltage to the heated seat relay.
5. This step tests for an open in the ground circuit to the heated seat relay.