Any tips and tricks on diagnosing what's wrong with A/C?

[07HBYaris]

I'm planning to get a new a/c compressor and was wondering if there are any tips or tricks to diagnosing A/C not blowing cold air. I don't want to purchase a compressor and that not being the issue. Thanks

[CTScott]

Techstream is the best way, as well as connecting a gauge set to check the high and low pressure sides of the system.

[07HBYaris]

Scott thanks for all the help all the time.

I've tried recharging, replaced evaporator, dyed lines.
I think the compressor is clutchless anyways, the engine revs up and tries to kick on the compressor and doesn't kick on so recharging was useless, replacing evaporator didn't change anything, dyed line reported no leaks.

Another question is would there by any chance a check engine light or anything of the sort be displayed on the dashboard that will let the driver know that there's something wrong with something like the A/C ecu or anything of the sort?

Also which techstream do you recommend?

[CTScott]

Scott thanks for all the help all the time.

I've tried recharging, replaced evaporator, dyed lines.
I think the compressor is clutchless anyways, the engine revs up and tries to kick on the compressor and doesn't kick on so recharging was useless, replacing evaporator didn't change anything, dyed line reported no leaks.

Another question is would there by any chance a check engine light or anything of the sort be displayed on the dashboard that will let the driver know that there's something wrong with something like the A/C ecu or anything of the sort?

Also which techstream do you recommend?


It could be a problem with the AC ECU. Unfortunately that won't show any kind of warning light, nor show on a normal diagnostic scanner.

For Techstream, I have heard of people having good luck with the cheap Chinese clones available on ebay. I personally use a Mongoose MFC, which I purchased back when they were about $700.

[07HBYaris]

Got the techstream ver. 9.10.038 yesterday and no DTC's concerning the A/C. I played with the magnetic relay pulley and all I got was just a higher engine rpm. Should I consider getting a compressor still? Any advice? Much thanks

[CTScott]

Got the techstream ver. 9.10.038 yesterday and no DTC's concerning the A/C. I played with the magnetic relay pulley and all I got was just a higher engine rpm. Should I consider getting a compressor still? Any advice? Much thanks

Can you do a screen capture with the data list shown for the AC so I can see what the numbers look like?

[07HBYaris]

Update:

Compressor seized. Got it R&R'd, paid alittle over $400 installed. Still has that starting/cranking noise from before but I have cold air now.

/thread

[tmontague]

Out of curiosity, did you ever not run your a/c or defroster for long periods of time?

Since the refrigerant carries the compressor oil, not using it can cause it to seize. I'm wondering if that was the potential cause here.