I have a 2001 accord dx that the a/c just stopped working. I did a search but there's as much info on the 98-02 accords like the 94-97 ones have. I am not getting power to the compressor or the condensor fan. The system is fully charged. The relay (M/G clutch in the underhood fuse box) is getting power, and clicks when I remove it and push it back in, and I have switched it with another known good one, and still nothing, so I'm pretty sure it's not the relay. The condenser fan fuse had blown, and was in pretty bad shape, the plastic had melted on it, had to remove it in a couple pieces. I am still getting voltage to the fuse location, up to 14v. but when I plug a new fuse (20amp) it still doesn't get any power to the fan. I have checked all other fuses related to the system, underhood and in-car, and I'm kinda at a loss at what to check next. If the pressure switch is bad will it keep the condenser fan/compressor from getting power? both the fan and compressor are good, jumpered them to make sure they work. I am going to pull the underhood fuse box out and pull it apart to see if the melted fuse might have done more damage than I'm seeing. any input on something I'm missing here is welcomed.

 

Probably will need a volt meter to do some of the tests. Unplug the pressure switch. See if the two pins on the pressure switch are a closed circuit. On the electrical connector, check that one pin has 12V to ground with the engine running and a/c turned on inside of the car. The other pin should have continuity to ground.

 

Something doesn't add up. You said the AC relay closes (presumably w/ AC switch on), but you don't get power to the compressor. The only way this could happen is damage to the wire from AC relay to compressor or faulty connector on this wire.

A relay can close but fail to make good contact, but you also swapped relays w/ same result.

Suggest checking compressor wire very closely for damage.

good luck

 

Ok well I did some more diagnosing, tested the pressure switch, gave me a 0.00 reading, which I believe is a closed circuit. probed the plug for the switch, gave me a reading of 4.70v. I'm not for sure what the correct voltage is, so if you guys know please inform me.

I also took the underhood fusebox out and took it apart to see if the melted fuse had done any damage underneath, but it looked fine. While I had it loose, I went ahead and turned the a/c button on and probed the wire at the connector for what I am pretty sure is the compressor power wire, and it is not getting any power from directly under the fuse box. It will give me a number like .1 or .2 but generally zeroes out at 0.00. The relay is getting power, and clicking when I pull it out and push it in.

This one has me stumped, for it was working perfectly, then went out the other morning to start the car and it wouldn't turn on. Any help is appreciated, cuz it's hot outside!! I'm gonna see if I can pick up a spare underhood fuse box and swap it in, see if that makes a difference.

 

When you say 0.00 on the pressure switch, did you test for voltage or resistance? You should test for resistance.

I am confused on your testing, so I'll just give you the tests that I would do.

Unplug the relay(s) you want to test.

On the relay electrical connector (usually 4 pins): Two of the pins should have 12V when the key is in the II position. One of the other pins will have continuity to ground at all times. The last pin will be open to ground when the a/c is turned off. It will have continuity to ground when the a/c is turned on.

Btw, what fuse melted? And more importantly, do you know why?

 

You're not sure which is compressor wire or which is compressor relay. You need to get a shop manual from somewhere; ebay (automanualsource), download from this site (Online Manuals links in DIY forum), or helminc.com.

For what it's worth the AC relay is usually near radiator or driver's side fender well, not in fuse box.

Working w/o a wiring diagram would stump anyone.

good luck

 

hey thanks for the help guys, I haven't had a lot of time to work on the car lately, gotten ahold of a few diagrams and such and done a little more testing. I have narrowed it down to the switch wire that runs to the relay from the PCM, pin A17, small red wire. I have continuity between the two points (PCM to relay), but there is no power coming from the PCM to the relay. My question now is should I be getting 12v coming from the PCM? I can touch the red probe of my multimeter to pin A17 (plugged into the PCM, car running, a/c switch on) and the black probe to a ground point and I get 0.00v. And if I am supposed to be getting 12v, does that mean the PCM is damaged?

 

Which relay are you testing and can you tell us wire colors?

 

ECM does NOT provide power to the relay. ECM provides ground to a constantly powered relay to enable power to be switched to the AC compressor. You must be guessing w/o a wiring diagram or not interpreting correctly. You could damage ECM if you attempt to jumper power to a ECM ground point.

I suggest you get some help. Your attempts to diagnose may cause more harm than help.

good luck