Hombre XS Space Cab L4-2.2L CPC (1997)
A/C Signal: Testing and Inspection
A/C Compressor Clutch Control Circuit Diagnosis
Circuit Description
The PCM receives an A/C request signal from the A/C selector switch. When A/C is requested, the Powertrain Control Module (PCM) provides a
ground path to the A/C clutch relay control circuit. When the relay circuit is grounded, the A/C compressor clutch relay is energized. The PCM
delays grounding the relay circuit for 0.3 second, so the PCM can adjust the engine idle RPM for the additional load.
The PCM will temporarily de-energize the A/C compressor clutch relay for one or more of the following conditions:
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A hot engine restart.
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A wide open throttle (TP sensor over 90%).
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Engine RPM greater than 6000 RPM.
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During an Idle Air Control (IAC) valve reset. The A/C compressor clutch relay will remain de-energized when one or both of the following
conditions exist:
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A DTC P0530 is set.
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There is no A/C request signal to the PCM. Refer to A/C diagnosis for more information on the A/C refrigerant systems.
Diagnostic Aids
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If DTC P0530 is set, do not use this table.
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An A/C refrigerant pressure outside the range of 43 to 426 psi, will cause the A/C compressor clutch to be disabled by the PCM. Observe the A/C
refrigerant pressure parameter on the scan tool for 2 minutes with the engine idling and A/C ON. If pressure goes out of range, refer A/C
Diagnosis.
Test Description