| DISCUSSION: A loss of A/C airflow and/or cooling
while the A/C blower fan continues to operate may be
experienced on some of the above vehicles.
The electrical signal from the A/C cycling clutch switch
passes through the Powertrain Control Module (PCM) to
engage and disengage the A/C clutch relay. If the PCM is
not properly disengaging the A/C clutch via the relay,
the compressor will stay on continuously and result in
evaporator freeze-up. Also, the PCM may not energize the
A/C clutch relay at all. This condition results in the
lack of cooling from the A/C system.
The PCM should be checked per the procedure in the
appropriate Powertrain Diagnostic Procedure Manual.
Diagnostic Trouble Code 33 (A/C clutch relay circuit)
will be present when either of these conditions are
caused by the PCM. It is important to perform the
complete test sequence because there are other A/C clutch
relay circuit components that could also cause or
contribute to the condition.
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