No. 23 A/C Does Not Work Sufficiently

POSSIBLE CAUSE

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

DIAGNOSTIC PROCEDURE

STEP

INSPECTION

RESULTS

ACTION

Connect the WDS or equivalent to the DLC-2.
Turn the ignition switch to the ON position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?

Yes

DTC is displayed:
Go to the appropriate DTC inspection.
(See DTC TABLE ).

No DTC is displayed:
Go to the next step.

Disconnect A/C compressor connector.
Start engine and turn A/C switch on.
Is there correct voltage at A/C compressor magnetic clutch terminal?
Specification
10.5 V or more

Yes

Inspect for GND condition of magnetic clutch on A/C compressor.
If GND condition is normal, inspect for open circuit magnetic clutch coil.

Go to the next step.

Disconnect refrigerant pressure switch connector.
Connect jumper wiring between A/C high pressure switch terminal.
Connect jumper wiring between refrigerant pressure switch terminal.
Turn the ignition switch to the ON position.
Turn A/C switch on and set blower fan to any speed.
Does A/C work?

Yes

Inspect refrigerant pressure switch operation.
If switch is normal, go to the next step.

Inspect for the following:

A/C switch is stuck open.
Open circuit in wiring harness between refrigerant pressure switch and PCM terminal 1AU⁽¹⁾, 1AP⁽²⁾, 1AU⁽³⁾
Open circuit in wiring harness between blower motor fan switch and resistor (if blower motor does not operate)
Evaporator temperature sensor and A/C amplifier

Remove jumper wiring from the switch connector.
Reconnect connector to refrigerant pressure switch.
Start the engine and turn the A/C switch on.
Does the fan operate?

Yes

Inspect whether A/C relay is stuck open.
Replace if necessary.

Inspect the following and repair or replace if necessary:

Refrigerant charging amount
A/C compressor for seizure

Verify test results.
- If normal, return to diagnostic index to service any additional symptoms.
  (See ENGINE SYMPTOM TROUBLESHOOTING ).
- If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
  - If vehicle is repaired, troubleshooting completed.
  - If vehicle is not repaired or additional diagnostic information is not available, Replace the PCM.
    (See PCM REMOVAL/INSTALLATION ).

⁽¹⁾	California emission regulation applicable model

⁽²⁾	Except for California emission regulation applicable model with LF engine ATX

⁽³⁾	Except for California emission regulation applicable model with LF engine MTX and L3 engine