Liberty 4WD V6-3.7L (2009)
Compressor Clutch: Description and Operation
A/C Compressor Clutch - Operation
A/C CLUTCH
The A/C clutch components provide the means to engage and disengage the A/C compressor from the engine accessory drive belt. When the
electromagnetic A/C clutch coil is energized, it magnetically draws the clutch plate into contact with the clutch pulley and drives the compressor shaft.
When the coil is not energized, the pulley freewheels on the clutch hub bearing, which is part of the pulley assembly.
A/C clutch engagement is controlled by the Powertrain Control Module (PCM). When the A/C-heater control is set to any A/C position, it sends a
request signal on the CAN-B bus to the Totally Integrated Power Module (TIPM), which then transfers the request on the CAN-C Bus to the PCM,
which determines if operating conditions are correct for A/C clutch engagement. When all operating conditions have been met, the PCM sends a signal
on a dedicated hard-wired circuit back to the TIPM to energize the internal A/C clutch high side driver. When energized, the A/C clutch high side driver
provides battery current to the A/C clutch field coil.
The A/C clutch control system is diagnosed using a scan tool See: Powertrain Management/Computers and Control Systems/Testing and
Inspection/Diagnostic Trouble Code Tests and Associated Procedures.
The A/C compressor clutch components cannot be repaired and must be replaced if inoperative or damaged.
