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B2753

Diagnostic Chart:




Schematic:




CIRCUIT DESCRIPTION
The body control module (BCM) controls the horn relay. The BCM grounds the horn relay control circuit in order to activate the horn relay. The BCM also monitors the horn relay control circuit to determine if it is shorted to ground or shorted to voltage.

CONDITIONS FOR RUNNING THE DTC
^ The BCM is commanding the horn relay ON (keyfob panic button pressed) or the horn switch is pressed.
^ Voltage supplied to the BCM is in the normal operating range (approximately 9-16 volts).

CONDITIONS FOR SETTING THE DTC
The horn relay control circuit is shorted to battery positive voltage for 250 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
^ The BCM disables the horn relay control for the remainder of the current ignition cycle.
^ The BCM stores DTC B2753 in the memory.

CONDITIONS FOR CLEARING THE DTC
^ A current DTC B2752 clears when the malfunction is no longer present and the ignition switch is cycled.
^ A history DTC clears after 100 consecutive ignition cycles without a malfunction present.

DIAGNOSTIC AIDS
^ If the horn relay control circuit is shorted to battery and the horn switch is pressed, a direct short to ground will result.
^ If the DTC is a history DTC, the problem may be intermittent. Perform the above tests while wiggling the wiring and connectors. This will often cause the malfunction to appear.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. Listen for an audible click when the horn relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. Tests for voltage at the coil side of the horn relay.
4. Verifies that the body control module and horn switch are providing ground to the horn relay.
5. Tests if ground is constantly being applied to the horn relay.