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NO.23 A/C DOES NOT WORK SUFFICIENTLY [WITHOUT WU-TWC]

id0103008029c6

23 | A/C DOES NOT WORK SUFFICIENTLY.
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DESCRIPTION | The A/C compressor magnetic clutch does not engage when the A/C switch is turned on.
POSSIBLE CAUSE | • Improper refrigerant charging amount • Open A/C magnetic clutch • Open circuit between A/C relay and A/C magnetic clutch • Poor ground of A/C magnetic clutch • Refrigerant pressure switch is stuck open. • A/C relay is stuck open. • Seized A/C compressor • Open circuit between A/C switch and PCM through both refrigerant pressure switch and A/C amplifier

Diagnostic procedure

STEP | INSPECTION | RESULTS | ACTION
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1 | Connect the WDS or equivalent to the DLC-2. Retrieve any continuous memory, KOEO and KOER DTCs. (See KOEO/KOER SELF-TEST.) Are there any DTCs displayed? | Yes | DTC is displayed: Go to the appropriate DTC test.
No | No DTC is displayed: Go to the next step.
2 | Disconnect the A/C compressor connector. Start the engine and turn the A/C switch on. Is there correct voltage at terminal for the A/C compressor magnetic clutch connector? Specification More than 10.5 V | Yes | Inspect for the ground condition of the magnetic clutch on the A/C compressor. • If the ground condition is normal, inspect for open circuit on the magnetic clutch coil.
No | Go to the next step.
3 | Disconnect the refrigerant pressure switch connector. Connect a jumper wire between the terminals of the A/C high pressure switch connector. Connect jumper wires between the terminals of the refrigerant pressure switch connector. Connect the WDS or equivalent to the DLC-2. Access the ACSW PID. Turn the ignition switch to the ON position. Turn the A/C switch on and set the blower fan at any speed. Does the ACSW PID read "on"? | Yes | Inspect the refrigerant pressure switch operation. • If the switch is normal, go to the next step.
No | Inspect for the following: • A/C switch is stuck open. • Open circuit between the refrigerant pressure switch and PCM terminal 1Q • Open circuit between the blower motor fan switch and resistor (if blower motor does not operate) • Evaporator temperature sensor and the A/C amplifier
4 | Remove the jumper wire from the switch connector. Reconnect the connector to the refrigerant pressure switch. Start the engine and turn the A/C switch on. Does the fan operate? | Yes | Inspect if the A/C relay is stuck open. Replace if necessary.
No | Inspect the following and repair or replace if necessary: • Refrigerant charging amount • Seized A/C compressor
5 | Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. • If the malfunction remains, replace or reprogram the PCM.