Acura TSX / Honda Accord CL. Manual - part 666

Fig. 81: Measuring The Voltage Between The No. 4 Terminal Of The Compressor Clutch 
Relay 4P Socket & Body Ground 

9. Turn the ignition switch OFF.  

10. Reinstall the compressor clutch relay.  

11. Make sure the A/C switch is OFF.  

12. Turn the ignition switch ON (II).  

13. Using a backprobe set, measure the voltage between the No. 18 terminal of ECM/PCM connector E (31P) 

and body ground with the ECM/PCM connectors connected. 

Is there battery voltage? 

YES: Check for loose wires or poor connections at terminal E18 of the ECM/PCM connector 
E (31P). If the connections are good, substitute a known-good ECM/PCM, and recheck. If 
the symptom/indication goes away, replace the original ECM/PCM.  

 

2004 Acura TSX 

2004 AUTOMATIC A/C SYSTEMS Climate Control System - TSX

  

 

NO: Repair open in the wire between the compressor clutch relay and the ECM/PCM.  

Fig. 82: Measuring The Voltage Between The No. 18 Terminal Of ECM/PCM Connector E 
(31P) & Body Ground (ECM/PCM Connectors Connected) 

14. Disconnect the jumper wire.  

15. Disconnect the compressor clutch 3P connector.  

16. Check for continuity between the No. 2 terminal of the compressor clutch relay 4P socket and the No. 2 

terminal of the compressor clutch 3P connector. 

Is there continuity? 

YES: Check the compressor clutch clearance, and the compressor clutch field coil (see 
COMPRESSOR CLUTCH CHECK ). Repair as needed.  

NO: Repair open in the wire between the compressor clutch relay and the compressor clutch. 

 

2004 Acura TSX 

2004 AUTOMATIC A/C SYSTEMS Climate Control System - TSX

  

 

Fig. 83: Checking For Continuity Between The No. 2 Terminal Of The Compressor Clutch Relay 
4P Socket & The No. 2 Terminal Of The Compressor Clutch 3P Connector 

A/C PRESSURE SWITCH & THERMAL PROTECTOR CIRCUIT 
TROUBLESHOOTING 

1. Turn the ignition switch ON (II).  

2. Press the AUTO button, then press the A/C button and check the display. 

Does the display indicate A/C on? 

YES: Go to step 3.  

NO: Check for loose or poor connection at the climate control connector. If the connections 
are OK, replace the audio-HVAC display panel.  

3. Disconnect the thermal protector 3P connector. 

 

2004 Acura TSX 

2004 AUTOMATIC A/C SYSTEMS Climate Control System - TSX

  

 

4. Turn the ignition switch ON (II).  

5. Measure the voltage between the No. 1 terminal of the thermal protector 3P connector and body ground. 

Is there about 5 V or more? 

YES: Go to step 6.  

NO: Go to step 20 .  

Fig. 84: Measuring The Voltage Between The No. 1 Terminal Of The Thermal Protector 3P 
Connector & Body Ground 

6. Turn the ignition switch OFF.  

7. Check for continuity between the No. 1 and No. 3 terminals of the thermal protector. 

Is there continuity? 

YES: Go to step 8.  

 

2004 Acura TSX 

2004 AUTOMATIC A/C SYSTEMS Climate Control System - TSX