Auxiliary Heater Element Relay: Description and Operation

DESCRIPTION





Three relays (1) are used for the electric Positive Temperature Coefficient (PTC) heater system when equipped with the 2.0L diesel engine. The relays are International Standards Organization (ISO) type relays. Relays conforming to the ISO specifications have common physical dimensions, current capacities, terminal functions and patterns (2). The PTC relays are electromechanical devices that switch fused battery current directly to the heating elements of the PTC heater unit. The PTC relays are located in the Power Distribution Center (PDC) and are energized by control circuits of the Body Control Module (BCM).