Air Conditioning not working in a 91 (1 Viewer)

[gorister]

I have read through the other threads and tried to figure out what is going on.

Just today my AC quit working (compressor quit coming on) and is therefor just blowing hot air.

I have read that sometimes the AC Temp Sensor switch would trip it off if the engine is overheating. And even though my guage does not show an overheating I removed the glovebox to disconnect the relay, and then started the rig to see if the compressor would come back on. No luck.

The coolant is fairly new, maybe 7k miles on it however it was down about a two inches in the overflow reservoir so I filled it up a little with some distilled water.

I am waiting for the truck to cool down to see if the compressor will come back on.

Anyone have any suggestions about what I should check or consider? Thanks.

 

[Rich]

Since you don't know where to start, I would suggest taking it to an AC shop. Perhaps you will find an AC tech who loves his job.

 

[MoJ]

Can't recall if my old 91 had the little window to check coolant or not.....if it does, you could start there.

 

[gorister]

Wow Rich....what great advice


My system is still using R-12. Since it happened suddenly while driving I have to assume it has something to do with the engine hitting the 266 degree mark or just a bad switch. I think I am going to start with a coolant flush tomorrow (wouldnt hurt even if that isnt the cause) and then from there I will start testing switches.

I think I tested the ac coolant unit succesful so I am just curious if there any other switches that could cause the trip to the compressor. Thanks in advance for any help.

 

[TX_TLC]

Since you are still on R-12 I wouldn't touch it unless you are licensed to do so....


So I would second Rich's advice...

 

[gorister]

I wont be touching any kind of charge/rechargeing equipment. That is why I am asking about switches.

 

[CJF]

Can't recall if my old 91 had the little window to check coolant or not.....if it does, you could start there.

You mean the sight glass to check the refrigerant level (pressure)? Won't help if the compressor's not engaging.

CJF

 

[CJF]

Since you are still on R-12 I wouldn't touch it unless you are licensed to do so...

Why not?

gorister,

I don't have any specific tips for you (my 91's AC is still chugging along), but it seems to me you're on the right track; you need to determine whether there's a switch/sensor that is bad or whether it is the compressor itself.

Hang in there (I'd say "Be cool" but, well, you know ),

CJF

 

[gorister]

CJF,

Mine was chugging along great too.......until today. Use to be the AC would freeze me stiff. Now I am stuck riding around in in 90 degree weather with 100% humidity. Blah.

I will try and conquer this thing tomorrow. First by coolant flush just to make sure I dont have any overheating and then with a swith/relay test.

Thanks for the advice CJF.

 

[Tentsontop]

AC temp sensor

I had the same problem. I think I read the same thread you mentioned earlier. I went out and disconnected/connected the sensor a few times and now it's blowing cold again. I guess I won't be doing the R134 conversion after all. Mine looked like a little oil got on it and may have caused it to wig out a bit. It's all good now though. I'm going to order another sensor just in case and clean the head/block a bit.

 

[gorister]

Jenny,

Interesting. I dont think I pulled the same switch as you. Where is there you are talking about? The one I pulled was inside the vehicle right next to the ECU. Thankfully some new light into my search for the problem.

 

[Tentsontop]

Email

Sent you a couple emails. Sorry it took me awhile to get back to you.

 

[PHAEDRUS]

Gorister,
if your coolant temp gauge got above the (well at least on my truck) 2/3 mark my ac will shut off.
You stated that you added coolant to the reservoir, Have you been having issues with the truck running hot??
I would check in that direction as the symptom you are trying to beat might be the signal from a far worse root cause. if the needle gets within a 1/4 of the total range of motion for the temp gauge then your ac should be shutting off.
course' I might just be paranoid about the cooling system on my truck.
Dave

 

[CJF]

Phaedrus,

You have a 92? I didn't think FJ80's had that feature, though I sure as h*ll wish they did (even with the trouble they seem to cause). Where is the sensor located? FSM page reference maybe?

Thanks,

CJF

 

[gorister]

Jenny Cruiser...thanks for the emails. Hopefully I can get this figured out before too much longer. Im sweating my ass off.

I havent had any issues with overheating and my temp needle hasnt budged. I read where Cdan wrote that the needle isnt that accurate though.

My AC just doesnt come on at all...no matter what temperature the engine is at. I am almost at a lost for what it could be. It was blowing ice cold one minute and then just stopped all of a sudden. Would this happen if the system just needed a simple recharge?

Any other ideas for diagnositcs. I hate to think I might have to pay someone to figure this out

Once again...thanks alot everyone

 

[CJF]

Gorister,

Do you have a Factory Service Manual? Gotta have one if you want to be able to track down stuff like this.

First three items in troubleshooting section are:

1) Fuse

2) Magnetic clutch relay

3) Inspect volume of refrigerant

(#4 says "Inspect refrigeration system with manifold gauge set", whatever that means )

CJF

 

[gorister]

I was hoping my rig would never be troublesome enough to need an FSM. Wishful thinking.

I dont have an FSM but I do have a Chilton (err...maybe it is Haynes) guide. I have been in and out of that book and cannot find any sort of help.

 

[CJF]

Ok Gorister: This is it, and then I'm done with you, only because I don't think there's much else you can do without a FSM (Is there one online here for our year? I don't know.), or a gauge set, or taking it to $omeone.

As stated above, check the fuse and the magnetic clutch relay (I just realized you're going to ask me where that is ...), and then the only other thing I can think of, and I'll probably get yelled at by someone for even suggesting it, is:

Attempt to discharge a LITTLE refrigerant SLOWLY from the compressor (either charge valve, I think, as long as it's not running). If you got nothing, you probably popped a seal somewhere; if you got something, well, like I said; I still don't know where you'd go from there, but at least you'll know whether you've got any r12 left in the system.

Hang in there, and sorry for my sarcasm; I don't really mean anything by it. ;p

CJF

 

[gorister]

Ah damnit

Just had to break down and purchase a FSM. Could only find one for a 92 so hopefully it will be the same stuff.

CJF....no worries man. I dont need sarcasm...just a good kick in the ass.

 

[gorister]

Finally today I drove around without leaving sweat marks in the seat.


I talked with the Cruiserhead I bought the rig from to see if he had ever run into any issues. He told me to check basic fuses and also to check the pressure switch witch is located right next to the left headlight. I didnt even know this cruiser had such a switch. So there I go out to check to see about jumping the switch that way I would atleast know if the system had sufficient charge. Well as I look at the switch I see the problem. The damn thing was unplugged. I dont know how it happened but I am just glad this turned out to be a simple type of fix.

Just goes to show you...always make sure to check the basics.