[aldo]

Hi folks my air cond compressor seems to have stopped. From working very well on my last drive about 3 weeks ago it, the compressor isn't cutting in anymore. The usual issues of water and mud entry problems don't apply in this case.

I have checked for refrigerant leaks, under dash fuse, swapped relays, pulley belt and unclipped (thinking of a bad connection) checked and plugged back in the connection for the pressure switch and the connection on the compressor.

Apart from that I don't know what else to try. The wire which runs from the back of the alternator to the compressor is a single wire, is it a 12 volt wire? I was going to try and stick a multimeter in it to see what happens.

The blue air cond light in the dash switch activates but that is about it.

 

[Richo]

IIRC doesnt the air con shut off if the engine temp climbs too high?
Maybe its a temp sender issue?

Try wiring the air con clutch/engagement wire straight to the battery and see if it engages.
Could also be the air con relay circuit.

 

[aldo]

Hi Richo, thanks for the ideas.

Just before I give them a try I have been out doing some more fiddling.

I guess that a pressure switch merely provides continuity to a circuit provided there is pressure right??

I used the ohms section of the multimeter and found that when I bridged the two contacts of the pressure switch I got no change to the reading as oppossed to simply contacting the two multimeter prongs accross each other. That would tell me the swicth is either faulty or the system has no pressure

What do the two H and L caps on the air cond pipes mean? I took the H cap off and gave the valve the slightest touch and a pretty weak hiss escaped. I guessing H meant high and it should have came out a lot stronger?? Still if the system has lost gas I can't see where the hell it has come from.

I was thinking of shorting across the two pressure switch terminals momentarily to see if the compressor kicks in, what do ya reckon?

 

[Nizzbits]

H is high pressure and L low pressure.
You say you checked for leaks. How did you do that? It sounds like you have no (or bugger all) gas. If it escaped (and has no dye in it) you would be unlikely to be able to see where it escaped.
If there is no pressure (see no gas) the low pressure switch will not allow the compressor clutch to kick in.

 

[MudRunnerTD]

H is high pressure and L low pressure.
You say you checked for leaks. How did you do that? It sounds like you have no (or bugger all) gas. If it escaped (and has no dye in it) you would be unlikely to be able to see where it escaped.
If there is no pressure (see no gas) the low pressure switch will not allow the compressor clutch to kick in.

x2 what he said mate, NO GAS for sure.

 

[aldo]

Hi fellas. The system does have the green dye in it.

I checked for leaks by running my hands with a clean white cloth over all the joins in the pipes around the engine bay.

Can't see too many issues. I rang the fella and I'm running it down to see what he can find under UV.

The system was flawless for the Patrols entire life and last year I had the clutch changed and the mechanic rocked the motor back and damaged the air cond pipe. This is the third issue I have had since. Annoys the crap outta me!!

btw Nizz I have forgotten to reply to you about the parts I need. This just reminded me.

 

[Frosty1970]

Sounds like it is dropping out on LP. More chance of it leaking out of the evaporator or TX valve under the dash than the solid fittings, if it's leaking. Take it to a fridgy and check the charge. Elliminate the easiest fix first.

 

[aldo]

Well you fellas were right. No gas left. The new pipe installed last year has fractured again.

 

[Nizzbits]

Well you fellas were right. No gas left. The new pipe installed last year has fractured again.

Must be either moving/rubbing or under too much pressure/strain me thinks.

 

[paul.helm]

Well you fellas were right. No gas left. The new pipe installed last year has fractured again.

Pictures of the offending pipe?

 

[aldo]

I'll be removing it in the next few days and I'll take a snap then. It's the pipe which runs across the firewall which has a union in front of the brake booster and runs across the firewall to a fitting infront of the passenger side.

The fracture appears to be right behind the engine, obscured by the air cleaner.

I'm considering using the two existing junctions and having just a few inches of aluminium piping before going into flexible piping so I don't have this happen again.

The replacement pipes from Nissan just never fit back the same way. They obviously install them when the engine bay is empty with easy access.

 

[harry6781]

My commodore just had the same prob. It was a crack in the high pressure side that leaked all of the A/C gas. One day it was fine the next it wasn't. The mechanic said it was probably due to a tiny front ender i had about a year ago.

 

[Don]

Just had a look at mine (2005 td42ti) & i reckon if i removed the intercooler & brackets & disconnect a couple of heater hoses it would slip in without having to bend it

How ever if you tried to thread it through without disconnecting all this stuff you might have some drama's

The trouble with the small high pressure alloy liquid pipes is that they are fairly flexible and it is tempting to bend them around to fit them without unbolting all the stuff you should to fit them correctly


Regards Don

 

[aldo]

Unfortunately when laying the new pipe and the old side by side they simply don't have the same exact shape. Remebering also mine is a non turbo GU with a Denco turbo fitted. The placement of the aircleaner really creates some issues with space at the rear of the engine.

Whilst I don't mind the turbo, the 90 degree turn of the air box is a pain in the bum.

 

[aldo]

Well it wasn't a fracture. It was a rub through. First through the usless foam type shielding then through the ally pipe.

I put quite a bit of extra covering over the pipe to protect it. I did this by using 10mm fuel hose. The bit I left to the original Nissan foam is where it failed. I'm a choko that needs to be slapped.

Ah well I really didn't need that $165.

 

[Squalo]

I suppose you are lucky that it was a relatively simple fix.

A mate in a 100 Series said that during his 6 month trip from Perth to Sydney via Darwin, he came across quite a few late GU's with total aircon failure. Bit of a worry, given that the aircon system is pretty lame to start with...

 

[aldo]

I just had the pipe welded. I'll wrap the entire thing in rubber and kevlar and hire a security gaurd to sit in the engine bay. I've become soft, summer in QLD is a shocker without aircond. Well it is since car manufacturers decided it was a smart idea to get rid of quarter windows

When you say the aircond is lame, do you mean not cold enough?

The one in the my GU, I'll jinx myself here for sure, is the coldest air cond I've ever experienced in any car. If we had a blackout I would just idle the Patrol in the garage and move all the meat out of the freezer onto the front seats. I'd chill my beer in it!!

 

[Sydo]

So up at Lancellin today and air con shat itself. Not kicking in. New compressor ?

 

[petefire427]

So up at Lancellin today and air con shat itself. Not kicking in. New compressor ?

Hey mate, start by pressing in the high shreader valve and see if there is gas in the system. If you get a strong jet then bridge out or connect 12v to the compressor and see if it clicks in and cools. If no gas check for leaks in the obvious spots, especially the condensor in front of the radiator, you may have staked it etc
let us know how you go with that and we will go from there.

 

[Sydo]

cheers mate