jicl55

My mom washed her 95 S320 and after that, no ac, no econo, no defrost, nothing. I figured it is a blower problem, but maybe it isn't? Checked all the fuses (driver's side under hood) and everything is fine. Bought a new blower motor and regulator, which wasn't the problem (plus the old motor was still good), and just replaced the AC control unit, and it still does not work! I can hear the flaps opening and closing when I move from min to auto to max, and we could get the blower to operate through the OBDI, but still not in the car. A short perhaps? How do I trace it or how else to test what it might be? Thanks for your help from a frustrated novice mechanic.

jicl55

So, either I just noticed it or it is just happening, fuse 21 (20A yellow) keeps blowing immediately when I try to turn on the air. This fuse is also connected to the tranny cooler and outside mirror and ac system. I tried doing a continuity test at the fuse itself, but it came up 0. What to do next? Should I pull the fuse box out and see what wires it is going to and start testing them 1 by 1? Does anyone have a wiring diagram so I can see what it is connected to? Thanks

oldsinner111

try the peachparts forum.They are more helpful.

Peter Guenther

The blower motor electrical source is different than you think, The posetive side goes to the motor, and the regulator is in series to ground. If the case has a poor ground it could cause your blower not to run. Try that approach

shopcarpro

Hi, Sorry about your trouble. If your fuse 21 is blowing when you turn on AC, there is an overload in that circuit. If you believe it was after the wash, there may be some water causing this problem,,, try blowing out with air any water accumulated,,, The problem may also disappear if the water evaporates with time and heat. Good luck.

DJ_VernonJ

Have to checked the blower motor relay?

jicl55

Blower motor, regulator and AC control unit were all fine and working. There must be an open short somewhere in the wires that is related to fuse 21. I could not find a wiring diagram that traces fuse 21 and where all the wires go. I know it is also involved with the headlight washing system and something else, besides the AC. Well, instead of trying to trace the short with no diagram, we rigged the AC control unit to be powered by the cigarette lighter and put in a bigger fuse for the cigarette lighter. So short not solved, but at least we have AC again.

Wanted to mention that the fuse would blow immediately once the car was turned on even if the AC was off.