A/C Compressor Clutch Circuit Troubleshooting
- 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 powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).
- Check the No. 12 (7.5 A) fuse in the under-hood fuse/relay box, and the No. 30 (7.5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES -Go to step 2.
NO -Replace the fuse(s), and recheck.
- Connect the HDS to the DLC.
- Start the engine.
- Turn on the A/C on the audio-HVAC display panel.
- Using the HDS, confirm the following values in the PGM-FI Data List at idle.PGM-FI DATA LIST REFERENCE
TP SENSOR About 0.5 V RPM 680 ± 50-750 ± 50 ECT SENSOR 2 176-212°F (80-100°C) A/C SWITCH ON A/C CLUTCH ON Are all the values within specifications?
YES -Go to step 7.
NO -Troubleshoot the value that is not within the specifications.
- Turn the ignition switch to LOCK (0).
- Remove the A/C compressor clutch relay from the under-hood fuse/relay box, and test it (see
POWER RELAY TEST
).
Is the relay OK?
YES -Go to step 8.
NO -Replace the A/C compressor clutch relay.
- Measure the voltage between the No. 1 terminal of the A/C compressor clutch relay 4P socket and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 9.
NO -Replace the under-hood fuse/relay box.
- Connect the No. 1 and No. 2 terminals of the A/C compressor clutch relay 4P socket with a jumper wire.Fig 2: Connecting No. 1 And No. 2 Terminals Of A/C Compressor Clutch Relay 4P Socket With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Does the A/C compressor clutch click?
YES -Go to step 10.
NO -Go to step 18.
- Disconnect the jumper wire.
- Turn the ignition switch to ON (II).
- Measure the voltage between the No. 4 terminal of the A/C compressor clutch relay 4P socket and body ground.Fig 3: Measuring Voltage Between A/C Compressor Clutch Relay Connector Terminals No. 4 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 13.
NO -Repair open in the BLK/YEL wire between the No. 30 (7.5 A) fuse in the under-dash fuse/relay box and the A/C compressor clutch relay.
- Turn the ignition switch to LOCK (0).
- Reinstall the A/C compressor clutch relay.
- Turn the ignition switch to ON (II).
- Make sure the A/C switch to LOCK (0).
- Measure the voltage between the No. 27 terminal of ECM/PCM connector E (31P) and body ground with the ECM/PCM connectors connected.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Check for loose wires or poor connections at No. 27 terminal of ECM/PCM connector E (31P). If the connections are good, check the ECM/PCM grounds. If the grounds are good, substitute a known-good ECM/PCM, and recheck. If the symptom/indication goes away, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).
NO -Repair open in the wire between the A/C compressor clutch relay and the ECM/PCM.
- Disconnect the jumper wire.
- Disconnect the A/C compressor clutch 1P connector.
- Check for continuity between the No. 2 terminal of the A/C compressor clutch relay 4P socket and the No. 1 terminal of the A/C compressor clutch 1P connector.Fig 5: Checking Continuity Between A/C Compressor Clutch Relay And A/C Compressor Clutch Connector Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Check the A/C compressor clutch clearance, and the A/C compressor clutch field coil (see A/C COMPRESSOR CLUTCH CHECK ). Repair as needed.
NO -Repair open in the wire between the A/C compressor clutch relay and the A/C compressor clutch.