Headlamp Relay: Description and Operation

The headlamp (or security) relay is a International Standards Organization (ISO) micro-relay. The terminal designations and functions are the same as a conventional ISO relay. However, the micro-relay terminal orientation (or footprint) is different, current capacity is lower, and the relay case dimensions are smaller than those of the conventional ISO relay.

The headlamp relay is a electromechanical device that switches battery current to the headlamps when the high-line [1][2]Central Timer Module ([1][2]CTM) grounds the relay coil. See Headlamp Relay in the Diagnosis and Testing for more information.

The headlamp relay is located in the relay and fuse block, which is located on the driver side end of the instrument panel in the passenger compartment. The headlamp relay cannot be repaired and, if faulty or damaged, it must be replaced.