Civic & Prelude
- Turn ignition off. Disconnect A/C pressure switch and A/C diode. See A/C SIGNAL COMPONENT LOCATIONS table. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminals No. 5 (Blue/Orange wire). If 5 volts (Civic) or battery voltage (Prelude) exists, go to next step. If specified voltage does not exist, go to step 4.
- Turn ignition off. Reconnect A/C pressure switch and A/C diode connectors. Turn ignition on. Using backprobe set, momentarily connect a fused jumper wire between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and No. 17 (Pink/Blue wire), several times. If A/C compressor clutch makes a clicking sound, go to next step. If A/C compressor clutch does not make a clicking sound, go to step 5.
- Start engine. Turn A/C and blower motor switches on. If A/C operates, A/C signal is okay. If A/C does not operate, go to step 7.
- Turn ignition switch off. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 5 (Blue/Orange wire). If continuity exists, repair short in Blue/Orange wire between PCM 31-pin connector "C" and A/C pressure switch. If continuity does not exist, substitute a known-good PCM and recheck. On Prelude, see SUBSTITUTING PCM in SELF-DIAGNOSTICS - INTRODUCTION article. On all models, if symptom or indication goes away, replace original PCM. If continuity still does not exist, inspect A/C system. See appropriate article in A/C-HEATER SYSTEMS.
- On Civic, using backprobe set, momentarily connect a fused jumper wire between ground and under-hood fuse/relay box 9-pin connector terminal No. 5 (Black/Red wire on CR-V), several times. See Fig 1. On Prelude, Using backprobe set, momentarily connect a fused jumper wire between ground and A/C clutch relay connector terminal No. 4 (Pink/Blue wire), several times. See Fig 1. See A/C SIGNAL COMPONENT LOCATIONS table. On all models, if A/C compressor clutch makes a clicking sound, repair open in Black/Red wire (Civic) or Pink/Blue wire (Prelude) between A/C clutch relay and PCM 32-pin connector "A" terminal No. 17. See WIRING DIAGRAMS article. If A/C compressor clutch does not make a clicking sound, inspect A/C system. See appropriate article in A/C-HEATER SYSTEMS.
- Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 5 (Blue/Orange wire). If less than one volt does not exist, repair open in Blue/Orange wire between A/C pressure switch and PCM 32-pin connector "A". If less than one volt exists, substitute a known-good PCM and recheck. On Prelude, see SUBSTITUTING PCM in SELF-DIAGNOSTICS - INTRODUCTION article. If symptom or indication goes away, replace original PCM. If specified voltage still does not exist, inspect A/C system. See appropriate article in A/C-HEATER SYSTEMS.
A/C SIGNAL COMPONENT LOCATIONS
| A/C Component | Location | |
|---|---|---|
| Accord | ||
| Clutch Relay | Under-Hood Fuse/Relay Box | |
| Pressure Switch | On Receiver/Dryer At Right Front Corner Of Condenser | |
| Civic | ||
| Clutch Relay | Under-Hood Fuse/Relay Box | |
| Diode | Under-Hood Fuse/Relay Box | |
| Pressure Switch | On Receiver/Dryer At Left Front Corner Of Engine Compartment, Next To Power Steering Fluid Reservoir | |
| CR-V | ||
| Clutch Relay | Under-Hood Fuse/Relay Box | |
| Pressure Switch | On Receiver/Dryer At Left Front Corner Of Engine Compartment, Next To Power Steering Fluid Reservoir | |
| Odyssey | ||
| Clutch Relay | Under-Hood Fuse/Relay Box | |
| Pressure Switch | On A/C Line At Right Side Of Engine Compartment, Under Fuse/Relay Box | |
| Prelude | ||
| Clutch Relay | Left Front Corner Of Engine Compartment, Next To ABS Modulator Unit | |
| Diode | Left Front Of Passenger's Footwell Under Middle Of Instrument Panel | |
| Pressure Switch | Next To Receiver/Dryer At Right Front Corner Of Condenser | |