AC clutch testing

[darek_u]

I have a constant problem with AC compressor that *I think* I traced down to faulty clutch. BM code 6 is present, sometimes also 7. Clutch is definitely not jammed, I can turn the compressor by hand with some effort, gap is also ok - 0.40mm. It looks like it doesn't want to engage. I found this in service manual:



I spent last hour trying to figure out how to use WIS but I failed miserably... Somebody got a big $$$ to make this program so complicated. Can someone help me out with this document? I will really appreciate...

 

[darek_u]

I can see it's not only me having trouble with pulling something from WIS... Anyway, I had a look at wiring diagrams and I can see that AC compressor clutch is fed directly from pin 20 of BM module. I'll try to connect battery voltage directly there, it would also allow me to check the current draw (should be 3.7A as per service manual) unless somebody has a better suggestion for me?

 

[darek_u]

For those who may come across this thread when troubleshooting similar problem - my clutch is fine, although the current draw is 2.45A compared to 3.75A value from service manual. It works fine anyway. The problem was located in Base Module - pin 20 feeding the clutch had a broken solder - it became obvious as soon as I opened the module and started to check the PCB. I also reflowed few more suspicious joints as well as cleaned the relay contacts (there are 3 relays inside). AC is freezing my a** off now