[CSDavies26]

Hey guys,

I just bought my 03 tracker back in December so this month is the first time I actually got around to looking at the AC....turns out that there's a problem...lucky me. It might be as simple as no freon in the system but I figured I'd ask you all and see if I can get pointed in the right direction for diagnosis. AC systems are one of the things that I don't have too much experience with on vehicles in general and I'd like to change that by fixing this problem myself...

Anyways, the little green light comes on as it should when the AC button is pressed...I hooked up a can of r134 with a gauge on it to the low side port and the gauge shot up to around 100-130 psi if i recall correctly. This is obviously way too high....the compressor is not cycling at all so I know that this high pressure reading is probably not accurate. I tried to put some freon in the system to see if that would get the compressor to come on, but it felt as if nothing was coming out of the can....

My question: Is there anything in particular that causes the low pressure side of the AC to give a high pressure reading? Or does my compressor not cycling mean that this reading is meaningless? Any good threads on this (I did some searching) or good places to start?

 

[fordem]

There is a dual pressure switch that disables the compressor clutch if it detects low or high pressure - it may be locking your compressor out - there is also the possibility that a previous owner has already tried what you are attempting.

You need to get a gauge set and measure the system pressures.

Another approach would be to wire a test lamp in place of the compressor clutch coil and jumper the pressure switch - if the test lamp comes on, remove the jumper - if the lamp goes off, the switch is locking out the compressor and you need to look at the pressures.

There are other reasons that the system will disable the compressor - we can explore these once we have established that the cause of the problem is not the pressure.

 

[CSDavies26]

Ok...I think they rent them out at advance auto so I'll go pick up a set from there...just from your experience, do our vehicles have any common problems with the ac system?

 

[Max]

The pressure you are observing is across the whole system when the compressor is not running.

What you saw was more than sufficient to meet the LOW pressure switch requirements, and not nearly high enough to trigger the HIGH pressure switch side. You've got other control circuit or clutch issues.

See this thread for tips, first off...
http://www.suzuki-forums.com/1g-199...ra/46612-2000-chevy-tracker-c-compressor.html

 

[Max]

do our vehicles have any common problems with the ac system?

No more so than any vehicle.

One (not really common) fault I've observed is one of the A/C lines near the condenser, held by a retaining bracket can chafe / hole the metal freon line. That's about it.

Curious...does your A/C condenser fan come on?

25 AMP fuse under the hood good?

How many miles on the compressor?

 

[CSDavies26]

Thanks for the link! I read through it and there's some good stuff there...

Anyway, I do believe I remember hearing the ac condenser fan come on...I didn't look at the tracker much this weekend because I am fixing up a Subaru to sell so much of my time has been devoted to that. I only hooked up the freon can w/ gauge to the tracker just to see if maybe I could get lucky and get the compressor to turn on by adding some refrigerant in. I didn't try to spin the clutch by hand yet or anything or checked any fuses/relays.

Hopefully I'll be able to get the Subaru listed for sale this week (waiting for the title to come in the mail - this was a quick buy and sell type deal) and then I can focus on this A/C issue next. It's supposed to rain every day this week so I probably won't look at it again until the weekend or sooner if the rain breaks :/ I'm assuming the compressor is original (atleast it looks to be based on exterior) so it has 134k miles on it. I did check all the lines for obvious corrosion/rust and all the lines actually look like they're in perfect shape.

 

[aquanaut20]

I have a similar issue with my AC (since mid summer last yr), the clutch coil is open....

Power to compressor, clutch will not engage..... Cannot find replacement coil and not into pulling compressor, so back to the 80-90's (drive at >30, windows down)..

.... Philip

 

[Max]

This might be you Naut'!

Chevy 10S11C A C AC Compressor Clutch Coil Two Wire | eBay

 

[CSDavies26]

Well I got around to checking out the simple stuff with my compressor...all the ground wires appear to be fine, the clutch spins if i move it by hand so the compressor isn't seized...the 25a fuse is good and the ac fan does come on when i push the button on the dash. Everything appears fine except for the fact that it won't engage! Grrr...maybe it's time for a new compressor? Should I try to force it to come on by jumping the switch?

 

[ElecTech]

I do a lot of refrigeration work although not much on cars. I may be able to help a bit though. I'm curious as to this part:

I hooked up a can of r134 with a gauge on it to the low side port and the gauge shot up to around 100-130 psi if i recall correctly

Was that with the engine compartment hot? If not, that's pretty high. Of course, I don't know how accurate those gauges are that come with the cans of R-134A anyway. This chart should give you an idea of what pressure you're looking for based on the temperature of the refrigerant. (The second column from the left if Fahrenheit and the light blue column is the corresponding R-134A pressure).

 

[Max]

Just to possibly clarify...those numbers / columns pointed out above are typical ambient system temperature corresponding to freon pressure, compressor not running (or completely in-operative).

The OP needs to find the reason why the compressor won't engage. The pressures exhibited by the OP's system are within the parameters for at least the system to start & run briefly.

The thread linked in post #4 will provide the troubleshooting tips needed to prevail. If still unsure or unable to proceed...seek professional A/C help CS.

 

[fordem]

the clutch spins if i move it by hand so the compressor isn't seized

All that proves is that the clutch spins - if the clutch coil isn't energized then the clutch doesn't engage and the compressor doesn't turn - which I believe is the problem.

...the 25a fuse is good and the ac fan does come on when i push the button on the dash.

I could be wrong on this, but I believe there are two fuses, you may need to check both.

Last but not least - see post #2 in the thread for specific recommendations.