94 E320 AC problem

Hm, is this one of the model years with the "environmentally friendly" wiring insulation that (bio)degrades?

Suggest that the wiring harness be changed out first. There have been other posts in this group about this problem, but HTH.

Cheers, WS

Was the car in a significant wreck?

If so, the electrical wires in the wreck site should be checked for abraded insulation, broken wires etc.

If not in a wreck I'd suggest you check the ground connections between the battery and the chassis, the chassis and the motor, the ground between the dash board and the chassis etc. etc.

Ghosts don't create intermittent events - and that's what's happening here, IMHO, - so you need to find the cause. The fact that the fuses are OK indicates no shorts so there's a break in the circuit - somewhere - and your task is to find the break.

The wiring harness first came to mind but its failure usually causes shorts and engine stalling (due to the disintegrating insulation). This problem, as described, is lack of continuity, not shorts.

It was involved in a significant crash but it was a rear left collision.. The funny thing is that this thing actually worked for about 30 minutes this morning. It wouldn't work again as assumed when I first tried it again today but after flipping the temperature to HOT then turning on the AC worked again, obviously including the fan. Then it stopped working altogether again. My wife's going to take it to our mechanic to see what can be done but thank you all for your comments.

I would check the overload relay unit... They had a bad batch of these at the same timeframe as your car... Check the date of manufacture on the side of the unit.

I would double check the ground... battery cable.

I had same problem on my 300E.

Tests showed that, under full load, the voltage was only 11.2V. Mechanic believed it was the alternator, since he had replaced the voltage regulator already. It is my understanding that the climate control 'problems' are actually safety cutoffs which engage when funny things like this happen.

In my case I felt it was time for the car to move on to it's next owner...

"" wrote: > hi there. my 94 E320 is having complete A/C failure. In > fact, even > the fan nor the heater works. It's basically anything related > to > climate control that failed miserably in this heat... The > local > mechanic says that all fuse seems to be in working order but > recommended that I take it to the dealer and get it fixed for > somewhere > around 400. Any thoughts on this?? This car's been having > constant > electrical problems to give you folks a bit of background on > this car. > One of the stereo channel's will mute then come back on > without any > indication of what happened, the windows sometimes stops > working then > starts working all of a sudden, again without any indication > of what's > wrong. I'm under the impression that since the fan isn't even > turning, > the electrical problem is somehow the culprit of all of my > problems and > the AC problem is just another cascading effect of this issue. > Can > someone please point me in the right direction? Thanks a > million. > > j

I had the same "issues" with my 94 E320 and it was the evaporator core......yikes.....hope you can DIY. Engine wiring harness will give weird engine codes.....and it will need to be replaced eventually. To check and see if the problem is the evap. core you can have the local A/C store put a die in the system then check for it "dripping" out under the car OR get a hydrocarbon based coolant (Pepboy?s etc) and install it. Usually come as a kit with the connectors. The hydrocarbo has an "odour" that if present IN the car is definitive for the evaporator. Good Luck

Had same problems with my '92. Mechanic said I was getting only 11.2V when everything was turned on. Said a new alternator or voltage relay was probably needed. Said the A/C has internal safeties which switch off if problems like this happen - so that condensation does not build up and lead to internal rust problems - and this will APPEAR to be A/C problems.

Since this is so much exactly like what I had, there may be some truth to it. Suggest you check freon and plan to put a heavy duty battery in, if yours is on the weak side.

Jan