Sebring Sedan V6-2.7L VIN R (2004)
Compressor Clutch Relay: Description and Operation
Description
A/C Compressor Clutch Relay
The A/C compressor clutch relay is a International Standards Organization (ISO) micro-relay. Relays conforming to the ISO specifications have common
physical dimensions, current capacities, terminal functions and patterns. The ISO micro-relay terminal functions are the same as a conventional ISO
relay. However, the ISO micro-relay terminal pattern (or footprint) is different, the current capacity is lower, and the physical dimensions are smaller
than those of the conventional ISO relay.
The A/C compressor clutch relay is located in the Power Distribution Center (PDC) in the engine compartment.
Operation
The A/C clutch relay is an electromechanical switch that uses a low current input from the powertrain control module (PCM) to control the high current
output to the A/C clutch electromagnetic field coil. The movable common feed contact point is held against the fixed normally closed contact point by
spring pressure. When the relay coil is energized, an electromagnetic field is produced by the coil windings. This electromagnetic field draws the
movable relay contact point away from the fixed normally closed contact point, and holds it against the fixed normally open contact point. When the
relay coil is de-energized, spring pressure returns the movable contact point back against the fixed normally closed contact point. The resistor or diode is
connected in parallel with the relay coil in the relay, and helps to dissipate voltage spikes and electromagnetic interference that can be generated as the
electromagnetic field of the relay coil collapses.
The A/C clutch relay terminals are connected to the vehicle electrical system through a receptacle in the Power Distribution Center (PDC). The inputs
and outputs of the A/C clutch relay include:
A/C Compressor Clutch Relay
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The common feed terminal (64) receives a battery current input from fuse 12 (40 amp) in the PDC through a fused B(+) circuit at all times.
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The coil ground terminal (60) receives a ground input from the PCM through the compressor clutch relay control circuit only when the PCM
electronically pulls the control circuit to ground.
-
The coil battery terminal (62) receives a battery circuit input from fuse 23 (20 amp) in the PDC through a fuse ignition switch output (run-start)
circuit only when the ignition switch is in the On or Start positions.
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The normally open terminal (63) provides a battery current output to the compressor clutch coil through the compressor clutch relay output circuit
only when the compressor clutch relay coil is energized.
-
The normally closed terminal is not connected to any circuit in this application, but provides a battery current output only when the compressor
clutch relay coil is de-energized.
The A/C compressor clutch relay cannot be repaired and, if faulty or damaged, it must be replaced. Refer to the appropriate wiring information for
diagnosis and testing of the micro-relay and for complete HVAC wiring diagrams.
