I have a question....On my 03 Jetta, at the thermo switch, I jump 1 and 2 and the low speed fans come on, but as per step 2, key on A/C button off, jumping 2 and 3 does nothing. When I jump it, it sends power on that wire to the fcm but nothing to the fans. Also no power to the compressor clutch at any time, all fuses are good. I can apply battery to fans and both speeds work fine. So, I'm thinking I have an fcm issue or a bad wire between the fcm and the fan. So I pull off the fcm and at the tabs base, the plastic is looking kinda burnt and the tabs are corroded. I clean it all up and get the tabs shining and still nothing. The burnt areas concerned me so I ordered one thru IDParts. Install new one and everything is still the same. Now I'm pretty convinced there is a wire issue between fcm and fan. Am I on the right track?
Backing up just a bit, One day my A/C is really cold, next day nothing but warm air. Turned key on, fan on and A/c button on and no cooling fans fans. The cooling fans were working a few weeks ago when I did this. I did notice that the last time the a/c worked, when I first turned it on, it was like the clutch was coming on and off really fast like a bad connection. I turned it off, waited a couple minutes and then turned it on and all was well. The next day nothing! Any suggestions would be greatly appreciated. Thanks in advance!!!