A/C Compressor Clutch Circuit Troubleshooting
A/C Compressor Clutch Circuit Troubleshooting
NOTE:
It is normal for the A/C compressor to turn off under certain conditions, such as low idle, high engine coolant temperature, or hard acceleration.
Do not use this troubleshooting procedure if the fans are also inoperative with the A/C on. Refer to the symptom troubleshooting index.
Before doing symptom troubleshooting, check for PGM-FI DTCs.
1.
Fuse check:

Fuse check
?1.
Check the following fuse.
Fuse
No. A17 (7.5 A)
Location
Under-hood fuse/relay box

Is the fuse OK?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Replace the fuse, and recheck. If the fuse blows again, repair a short in the No. A17 (7.5 A) fuse circuit.?
2.
A/C pressure threshold check:

A/C pressure threshold check
?1.
Connect the HDS to the DLC.

?2.
Start the engine.

?3.
Set the A/C button and the blower control dial to ON.

?4.
Using the HDS, check the following conditions:
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
ENGINE SPEED
K24W1 engine (M/T):
730?830
rpm
    
K24W1 engine (CVT):
670?770
rpm
    
ECT SENSOR 2
80?100
°C
    
176?212
°F
TP SENSOR
About 0.5
V
    

?5.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
A/C PRESSURE SENSOR
196?3,138
kPa
    
2.00?32.00
kgf/cm2
28.4?455.1
psi

Do the current condition(s) match the threshold?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
Go to the A/C system test.?
3.
HVAC control system check:

HVAC control system check
?1.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
A/C SWITCH
ON
      
A/C CLUTCH
ON
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
     
NO
     
     
     
A/C SWITCH is ON and A/C CLUTCH is OFF, update the PCM if it does not have the latest software, or substitute a known-good PCM, and recheck.?
4.
A/C compressor clutch relay check:

A/C compressor clutch relay check
?1.
Turn the ignition switch to LOCK (0).

?2.
Remove the A/C compressor clutch relay from the under-hood fuse/relay box, and test it.

Is the relay OK?

     
YES
     
     
     
Go to step 5.
     
NO
     
     
     
Replace the A/C compressor clutch relay.?
5.
Open wire check (+B MG CLUTCH line):

Open wire check (+B MG CLUTCH line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
IG LOCK (0)
A/C compressor clutch relay: disconnected
Test circuit
+B MG CLUTCH
Test point 1
A/C compressor clutch relay 4P socket No. 1 (TAN)
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The +B MG CLUTCH wire is OK. Go to step 6.
     
NO
     
     
     
Repair an open in the wire between the No. A17 (7.5 A) fuse in the under-hood fuse/relay box and the A/C compressor clutch relay.?
6.
Determine possible failure area (A/C compressor clutch relay switch side circuit, A/C compressor clutch relay coil side circuit):

Determine possible failure area (A/C compressor clutch relay switch side circuit, A/C compressor clutch relay coil side circuit)
?1.
Connect terminals A and B with a jumper wire.
Terminal A
A/C compressor clutch relay 4P socket No. 1 (TAN)
Terminal B
A/C compressor clutch relay 4P socket No. 2 (RED)


Does the A/C compressor clutch click?

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
Go to step 9.
7.
Open wire check (IG2 A/C line):

Open wire check (IG2 A/C line)
?1.
Disconnect the jumper wire.

?2.
Turn the ignition switch to ON (II).

?3.
Measure the voltage between test points 1 and 2.
Test condition
IG ON (II)
A/C compressor clutch relay: disconnected
Test circuit
IG2 A/C
Test point 1
A/C compressor clutch relay 4P socket No. 3 (LT GRN)
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The IG2 A/C wire is OK. Go to step 8.
     
NO
     
     
     
Repair an open in the wire between the relay circuit board and the A/C compressor clutch relay in the under-hood fuse/relay box, or between the No. B1 (7.5 A) fuse in the under-dash fuse/relay box and the relay circuit board in the under-hood fuse/relay box. If wires are OK, replace the relay circuit board.?
8.
Open wire check (A/C MG CLUTCH RLY CL- line):

Open wire check (A/C MG CLUTCH RLY CL- line)
?1.
Turn the ignition switch to LOCK (0).

?2.
Reinstall the A/C compressor clutch relay.

?3.
Jump the SCS line with the HDS.

NOTE: This step must be done to protect the PCM from damage.

?4.
Disconnect the following connector.

?5.
Connect terminals A and B with a jumper wire.
Terminal A
PCM connector A (51P) terminal No. 13 (PUR)
Terminal B
Body ground


?6.
Turn the ignition switch to ON (II).

Does the A/C compressor clutch click?

     
YES
     
     
     
Update the PCM if it does not have the latest software, or substitute a known-good PCM, and recheck.?
     
NO
     
     
     
Repair an open in the wire between the A/C compressor clutch relay and the PCM.?
9.
Open wire check (A/C MG CLUTCH line):

Open wire check (A/C MG CLUTCH line)
?1.
Disconnect the jumper wire.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0)
A/C compressor clutch relay: disconnected
A/C compressor clutch 1P connector: disconnected
Test circuit
A/C MG CLUTCH
Test point 1
A/C compressor clutch relay 4P socket No. 2 (RED)
Test point 2
A/C compressor clutch 1P connector No. 1 (RED/WHT)


Is there continuity?

     
YES
     
     
     
     
NO
     
     
     
Repair an open in the wire between the A/C compressor clutch relay and the A/C compressor clutch.?