NO.23 A/C DOES NOT WORK SUFFICIENTLY [L3]

BME010300103261

23

A/C DOES NOT WORK SUFFICIENTLY.

DESCRIPTION

A/C compressor magnetic clutch does not engage when 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 GND 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

1
Connect the WDS or equivalent to the DLC-2.
Retrieve any continuous memory, KOEO and KOER DTCs.
Are there any DTCs displayed?
Yes

DTC is displayed:

Go to the applicable DTC inspection.
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 of the A/C compressor magnetic clutch connector?
Specification

More than 10.5 V

Yes
Inspect for GND condition of the magnetic clutch on the A/C compressor.
If GND condition is normal, inspect for open circuit of the magnetic clutch coil.
No
Go to the next step.
3
Disconnect the refrigerant pressure switch connector.
Connect a jumper wire between terminals of the A/C high-pressure switch connector.
Connect a jumper wires between terminals of the refrigerant pressure switch connector.
Connect the WDS or equivalent to the DLC-2.
Access AC_REQ PID.
Turn the ignition switch to the ON position.
Turn the A/C switch on and set the blower fan at any speed.
Does AC_REQ PID read ON?
Yes
Inspect refrigerant pressure switch operation.
If switch is normal, go to the next step.
No
Inspect for the following:
• A/C switch is stuck open.
• Open circuit between refrigerant pressure switch and PCM terminal 1AC
• Open circuit of blower motor fan switch and resistor (if blower motor does not operate)
• Evaporator temperature sensor and A/C amplifier
4
Remove a jumper wire from the switch connector.
Reconnect connector to the refrigerant pressure switch.
Start the engine and turn the A/C switch on.
Does the fan operate?
Yes
Inspect for stuck open A/C relay.
Replace if necessary.
No
Inspect the following and repair or replace if necessary:
• Refrigerant charging amount
• A/C compressor for being seized
5
Verify test results.
• If normal, return to diagnostic index to service any additional symptoms.
• If malfunction remains, replace PCM.