Honda Civic A/C issue

[MTL_4runner]

Well, wouldn't you know it!

Right after I finished fixing the alternator my AC on the Civic decides to quit on me. I immediately thought it might have had a leak so i got a set of AC gauges to check the pressure and it turned out to be fine. Next I checked the pressure switch on the drier by jumping the leads and it failed to kick on the AC compressor. I also verified across the switch terminals that it had continuity, and it did. I tried jumping the clutch on the compressor and that worked too so I was stumped. Well, when I went to book an appointment with the Honda dealer and described what I did, the service manager immediately said "yeah, it's probably the thermal protector". I think this is one I'm just going to let them repair, but I'll post back on what the fix finally was when it gets solved.

[MTL_4runner]

In case someone else with a Honda is diagnosing their AC, I found this to be very helpful:
.....the really great part about the article is they take the view of the garage!

Cool Under Pressure
by Bob Dowie

"It still surprises me that the customer who contemplates having a CV boot or timing belt replaced does not hesitate to spend the money to have the air conditioning repaired.

Many of our customers consider air conditioning to be a necessary, rather than an optional, vehicle amenity. For this reason, it has to work on demand. Why shouldn’t your shop garner these A/C service and repair opportunities? To aid your efforts, this article is going to look at some of the most common A/C problems we encounter on the Honda vehicle lineup.

While this article focuses on Honda models, much of the information here applies to other nameplates, as well.

While you’re pulling your customer’s car into the bay, you can start the diagnostic process. Operate the heater and A/C controls. Does everything move smoothly? Pay close attention to rotary-style heater control knobs. They can crack along the shank that slides onto the heater control shaft. If in doubt, pull it off and take a look. This issue has tricked more than one good technician. Of course, the same problem will cause a “no heat complaint” in the fall.

While you were operating the A/C controls, what else were you looking for? Did the indicator light by the A/C switch light up? Did you hear the compressor clutch close? Did it stay engaged? Did the idle step up in anticipation of the compressor dragging it down, or did the cooling fans start to run to increase the airflow over the condenser? Don’t forget to check blower motor operation, as the ground circuit for the A/C system is provided by the fan switch. Don’t forget that if the fan switch is off, the A/C is also off.

Pressure Checks/Leak Detection

With the reliability that Honda enjoys, it’s a safe bet that you got some indication that the A/C system was willing to work for you but needs some service to cool your customers. But, what if you didn’t get any signs that the system was trying to work? Either way, I would continue your diagnosis by checking the system pressures.

Honda, like all other carmakers, protects the compressor with a low-pressure switch that opens the power lead to the compressor when the system pressure is low. If the pressures are very low, take the time to visually inspect the system for obvious leaks. Look for broken lines, loose fittings or damage to the lines or condenser from collision damage. At the same time, look for the telltale stains of compressor oil.

In the last few years, we’ve all become accustomed to using the various dye kits that are available for leak detection. Although these products work well, they require installing the dye and charging the system to locate a leak. We can use the compressor oil in the same way. If you detect an area that is oily and dirty on the condenser or a fitting, it’s a safe bet that refrigerant is leaking along with the oil. Confirm the leak with a leak detector and you can make the repair without having to add refrigerant, only to remove it so the system can be opened.

We’ve found that the most common leakage problem on Hondas stem from the condenser. Usually, they leak in the corners, but with their exposure to road debris, it pays to give them a thorough inspection. In the older Hondas, we’ve seen some sight glasses and pressure switches that would leak. Again, look for the oil stain. Make sure that the pressure relief valve or plug did not blow off. Usually the customer will report that something seemed to blow out.

If you find evidence of excessive pressure, be sure to check cooling fan operation. Honda uses a couple of different methods to turn on the condenser fan. Some systems simply turn on the radiator and condenser fan when the compressor clutch is on, while others use a high-pressure switch that turns on the fan when the high side reaches a certain pressure. The method used isn’t as important as being sure that the fans run and the high-side pressures are not extreme.

A word of caution on selling Honda A/C condensers. It’s a good idea to make sure you’re able to remove the lines from the condenser before quoting the job and ordering the parts. With the longevity that Hondas enjoy, the aluminum fittings may have been together a long time, resulting in a real challenge to get them apart. You can spend a lot of time fighting with a fitting to get it apart, only to find the threads are unusable. The lines aren’t expensive and most dealers have the common ones in stock. But a little planning can avoid a disappointed customer. This is also the time to convert any R-12 systems to R-134a, as well as install a fresh receiver drier.

Compressor Dilemmas

What if the system was full and the compressor clutch still was not closing? Check the connector that goes to the compressor. Is battery voltage present? If so, probe the wire close to the clutch. No current here would indicate a problem with the thermal protection device in the compressor.

On some of the Civic models, there have been reports of problems with the clutches themselves. Some don’t work at all, while others work intermittently – they’ll engage the first time they get current, but may not re-engage as the system cycles. The problem seems to be affected by high ambient temperatures. Some technicians report good success with setting the clearance tighter between the magnet and the driven plate, while others report a bad ground between the compressor and the engine. Simple voltage drop checks will let you know if the ground is good.

At the same time, you might as well check the power lead for drops. If the voltage checks were good, I would recommend replacing the clutch and magnet unit.

It’s a tough job to remove the compressor, and the only way you’ll know whether closing up the clearance is going to work is to remove the compressor, tighten the clearance, and reinstall and charge the system. It’s too big a gamble for me to take. Sell the clutch unit and be sure of the repair.

The other side of the coin is a system that seems to have enough at rest pressure (40+ psi) to allow current to be sent to the compressor, but you find none. When you tested the controls, what did you find? No reaction to the switches would send me to the fuse box with a two-wire test lamp in hand to check all the fuses.

I find it easier to just check all the fuses rather than try to figure out which fuse works what. I like to use the two-wire light since even with the key on/engine off, some fuses will not have power. Since the two-wire light also shows a ground circuit, all the fuses can be tested.

If you find a blown fuse that gets the A/C working or one that blows as soon as it’s installed, make note of the number and you have a place to start when you get out the wiring diagram. No bad fuses would send me to my repair information source and wiring diagrams. We work on too many years and models of Hondas to try to cover them. The trick is to have good information on hand. The circuits are nothing tricky, but it’s hard to test whether the compressor relay is getting its ground, if you can’t find the relay on the car.

Suppose when you tested the controls, the indicator light illuminated and the idle stepped up, but the compressor clutch received no current. Since this is the same situation you had when the system was low on refrigerant, check that the pressure switches are getting the current you would expect according to the wiring diagram. On different models, these switches operate and look different. Some will be simple two-wire switches, while others may be dual switches that look at both high and low pressure. Other models may have more than one switch. Again, go to your service information source to locate and check these switches.

The last thing to check would be the A/C thermostat. Its job is to prevent evaporator freeze-up by cycling the compressor to control temperature. Mounted in the evaporator housing, these sensors are usually not a problem.

The Hidden Culprits

Another situation is that the A/C appears to be operating properly – clutch engaged, fans running and the blower motor works on all speeds – but you’re not getting cold air out of the vents. Sometimes this can be the most frustrating problem of the bunch. Don’t assume the vents are open and set to A/C operation. I’ve repaired many “I don’t get any cold air out of the center vents” complaints on older Accords by reminding the client to flip the lever back to the A/C position. But not all of the problems are that simple. Since you checked the operation of the controls earlier and didn’t think anything was amiss, you will have to dig a little deeper. Chances are something is not happening when you are telling it to.

The first place I would look is at the heater valve under the hood. Located in the inlet heater hose, its job is to shut off the flow of hot water to the heater core. Make sure that the lever on the valve is moving when the temperature control dial or lever is moved. It’s not unusual for the valves to stick in one position after being left in the heat setting for eight months. The customer may think that just a little extra effort might be all it will take to move it. Of course, something will move, but it’s usually not the valve. The cable may slip from its bracket, allowing the outer cable to move when the control is operated. Or, the inner cable bends, either at the valve or control unit.

Now is a good time to double-check the heater knob. Either way, the heater valve ‘thinks’ you are asking for warm air, and the A/C system gets the blame. In addition to controlling the water valve, the heater dial or lever also controls the operation of the blend or air mix door. Though it’s not as easy to check as the heater valve, it’s certainly not difficult to diagnose.

The blend door, as the name implies, directs the airflow that enters the car. If the door is not in the proper position, the air will not pass through the evaporator on its way to the vents. The most difficult part of the diagnosis is getting a look at the lever. Be sure there isn’t a problem as described when you checked the heater valve.

Although some cars exhibit the problem of the blend door sticking in the housing, Hondas don’t seem to have that problem. To be sure, you should be able to hear the door move as the lever is operated. Problems with the blend door are not very common. Most of the ones we’ve seen are a result of vandalism (a radio being stolen) or a head unit installed by less-than-skilled people.

Frozen Compressor

The last thing I’ll touch upon is the seized compressor. Although it is not nearly as common today as it was in the past, a locked-up compressor is not unlikely. It’s probably the easiest problem to diagnose. The heat damage is usually quite obvious, not to mention the noise the belt will make. The problem here is not replacing the locked-up compressor but rather how to sell the job and be sure you can provide a quality, profitable repair.

The problem is that when the compressor locked up, all of the pieces that resulted from the failed compressor entered the system and became lodged everywhere. What else should you replace with the compressor? At the very least, recommend a new receiver dryer – the filter of the system. It’s a safe bet that the expansion valve will be plugged. While you’re replacing the valve, be sure to flush the evaporator. It will be out anyway when you replace the valve.

Don’t forget about the condenser. In the best case, the above-mentioned pieces will be in there, waiting to make the return trip to your rebuilt compressor. In the worse case, the condenser is plugged solid. Either way, the safe thing is to replace it, flushing all the lines as you go.

The last thing you’ll need is to install an inline filter in the suction line at the compressor to catch any debris you missed during the clean-out process. I know at least one rebuilder who has made many of these steps mandatory to keep the warranty in place. Needless to say, we’re talking a lot of money here. Be sure the customer understands what he or she is getting into. There is no way to cut corners on this job. Don’t let the customer talk you into trying it.

I hope you feel better prepared to handle the Hondas – or any other marque – that finds its way to your door during the first hot days of this spring. There is no reason not to welcome this work.

Like everything else on a Honda, the A/C system is well-designed and reliable – generally. Problems can occur, and you need to take a measured approach to diagnosing and solving the problem. Remember: A cool customer is a happy customer!"


http://www.tirereview.com/?type=art&id=82174

[MTL_4runner]

Ok, I brought the Civic to the Honda dealer today because without an actual FSM, I'm not going to frig around with it anymore. I need A/C and I'm not going to sit there and sweat in the car on the way home from work everyday until I figure out how to solve it. I hope the repair won't drill too deep a hole in my wallet. We'll see when I pick it up tonight.

[MTL_4runner]

Got the Civic back and it was indeed the thermal protector on the A/C compressor. About $70 worth of part and an hour later I got out for $133 CDN with my A/C totally back and working. I need to throw the high/low side gauges on there to make sure it's fully charged, but I'm not going to be as picky as I would be with the 4runner.

[BennyTRD]

I had a leak in the bottom right hand side of the condensor in my 00 Civic. The little rubber seal was crimped when condensor was replaced by the Body Shop. I had unfortunatly cranked a small deer on the highway, and the condensor needed to be replaced along with some other cosmetic body parts. Good thing for wildlife coverage!!

[Duff]

I am new to this forum, found it while googling for help regarding A/C issues with Honda Civics. I have a 2000 Civic EX and the A/C blower fan has stopped working. For quite some time, it has not seemed to be putting out much air volume even with the recirculate buttom depressed. Also, it has been making a "clicking" sound when spinning, much like a sound made when motor bearings are failing or becoming worn. Several times turing on the air, the fan wouldn't start, and I found that "banging" on the underside of the fan housing underneath the passenger side dash would cause the fan to start up. It now won't spin up at all, so I assume the blower motor has failed. Have you had experince replacing the blower fan? I do alot of my own reapirs and would prefer to do this one. Any suggestions?

[MTL_4runner]

I am new to this forum, found it while googling for help regarding A/C issues with Honda Civics. I have a 2000 Civic EX and the A/C blower fan has stopped working. For quite some time, it has not seemed to be putting out much air volume even with the recirculate buttom depressed. Also, it has been making a "clicking" sound when spinning, much like a sound made when motor bearings are failing or becoming worn. Several times turing on the air, the fan wouldn't start, and I found that "banging" on the underside of the fan housing underneath the passenger side dash would cause the fan to start up. It now won't spin up at all, so I assume the blower motor has failed. Have you had experince replacing the blower fan? I do alot of my own reapirs and would prefer to do this one. Any suggestions?

I'd bet money that the blower fan either has severely worn bushings or the motor's brushes are worn out. In any case your blower motor is definately toast and my suggestion to you would be to either get a used fan from a local junkyard (even if they don't have one they'll get one for you through the national parts database) or just get one new from the dealer.

Here's the best place I've seen for getting OEM Honda parts:
http://www.hondaautomotiveparts.com/...=HEATER+BLOWER

The replacement of it will take some time if you do it yourself, but definately doable.

[a_l_e_x1]

In my case, tested all the AC-related relays and fuses. The red wire going to the temp control sensor is fine and there's 14 volts on the Field Coil when the car is running and the AC in ON.
The air is still warm and the heat exchanger (under the glove box) doesn't get cold.
Got 2 cans of R134a-compatible gas and filled the system, same problem
Then the AC is turned on, the RPMs go higher (from about 700 to about 1200) and go to idle slowly. When it is turned off, the RPMs go high again (to about 1000), then drop to 700 slowly.
Any help??
Since I got this car (2 years ago), the AC never worked.
I also for the Haynes manual and the original Honda manual. Tried everything there, no help.

[MTL_4runner]

In my case, tested all the AC-related relays and fuses. The red wire going to the temp control sensor is fine and there's 14 volts on the Field Coil when the car is running and the AC in ON.

The air is still warm and the heat exchanger (under the glove box) doesn't get cold.

Got 2 cans of R134a-compatible gas and filled the system, same problem
Then the AC is turned on, the RPMs go higher (from about 700 to about 1200) and go to idle slowly. When it is turned off, the RPMs go high again (to about 1000), then drop to 700 slowly.
Any help??

Since I got this car (2 years ago), the AC never worked.
I also for the Haynes manual and the original Honda manual. Tried everything there, no help.

Ok, so help us out here.....what vehicle do you even have? year? model? engine?

The very first thing you need to do is get yourself a good set of AC manifold gauges right away if you really want to work on your own A/C at all. If you don't then just take it to a shop or dealer because you're not really serious about working on the A/C if you don't want to invest in the correct tools for troubleshooting.

Harbor Freight sells a cheap set if you don't want to spend alot on them:
http://www.harborfreight.com/cpi/cta...emnumber=92649



Now why eaxctly did you fill the system with more refrigerant? I'll have to assume you never put a set of manifold gages on it to check the pressures in the system. Did you test the pressure sensor to verify if you have continuity or not? Did you jump the pressure sensor connection to see if the AC clutch kicked on? I assume in all this that the AC clutch is not kicking on at all despite the idle up....if it is then you need to get a set of gauges on there to see what the pressures look like. Once you get those, post them and we can help.

You should take it to a shop and have them immediately evacuate all the R-134a in the system, hold a vacuum and then recharge with the proper amount of refrigerant (by weight!!!!). If you overchaged it that badly, you can definately cause major damage to the system. You need to get that taken care of asap.

More help on troubleshooting:
http://www.aa1car.com/library/ac98.htm

[SVTour98]

Hey guys, maybe you can help my wife and I out. I came across this thread while googling for info on an AC problem.

My wife has a 2003 Honda Civic EX. She noticed about 2-3 weeks ago that the AC was not working. She said the car was not cooling down. I wrote it off because it was 95+ degrees out and just assumed the AC was struggling as it might (black on black car so it gets very hot inside). Anyhow, I was in the car today with her when I realized the AC was blowing hot air (not heated air, but hot as in outside hot air). She thinks the AC was working the night before, but again I don't know for certain. It may have been just recirculating cooler outside air and she thought it was ok. So in short, I haven't a clue when the last time it fully worked.

What I noticed is that the AC compressor does not cut on. The clutch does not engage. The AC light in the dash is "on" and I tried many different settings (defrost, vents, etc..) but no luck. I tested the pressure sensor for continuity and it is fine (as such jumping does nothing either). I got a pressure gauge from Pep Boys and tested the system and it is in the normal range (since the compressor is not cutting on). Also the RPM's do not increase when the AC switch is pressed. They stay in the same 700ish range.

I had read online that maybe the AC "on" switch may not be working correctly having something to do with the ambient temperature in the car. Here is what he wrote:

http://autoforums.carjunky.com/autof...t_hot_!!_P887/


"I finally fixed the problem, although I have wasted $$ to replace the ECU, thermo switch. Too bad that I did not look at the circuit diagram carefully at first. The problem is the AC switch in the HVAC. The swtich's light lights up okay, but in fact the control circuit is open when the cabin temp is high.

I pulled out the HVAC control module and tested the AC switch around sunset. It has no continuity. But when I tested in around midnight, it has continuity. So it explains the intermittent problem."

I don't quite understand that but it was described online in a few places. My wife is pretty certain that the AC worked the other day in the morning when she drove to work (she recalls turning it down because it was getting too cool), so tomorrow morning when it's a bit cooler I'll try it and see if the compressor cuts on. I haven't even a clue how to get that HVAC console/dash out to even get to the AC switch so I can test it for continuity. I tried prying up with a flat screwdriver around the edges of the plastic but it was not budging (didn't want to damage the dash either).

Anyhow, are there any other tests I can do? I tested all of the fuses under the hood and in the fuse panel under the steering column. They are all good. Any help is appreciated in this 95+ degree weather...