Cleaned Engine bay now cc blower won't blow - PeachParts Mercedes-Benz Forum

Phillytwotank · #1 05-03-2014, 10:04 AM

I had some free time at work yesterday so I decided to give the blues mobile some TLC. With the help of two great products I was able to get it looking great under the hood. I forgot to get a good before picture.

Problem is now... The blower won't blow with the engine running. It will come on and blow with the key in the "run" position.

I've checked the fuses. Any other ideas where to look for the problem?

Zacharias · #2 05-03-2014, 11:04 AM

Questions:

- Is defrost working all the time, or only with the rest of the system?

- When you start the car and the cc isn't working, have you tried to see if other accessories are all working?

- And have you tried gently moving the key to the left with the motor running, to see if the cc starts?

My 300d does this on an intermittent basis. I plan on replacing the ignition switch soon and my key tumbler immediately, as it is also worn. Sometimes I have to nudge the key back to the left a little after starting, to get power to the cc system and some other accessories.

Phillytwotank · #3 05-03-2014, 11:08 AM

Negative. I can feel the compressor clutch engage in defrost and AC modes but no blower in any mode.

Worked proper before the engine bay cleaning.

Guest987 · #4 05-03-2014, 12:51 PM

Maybe leave in out in sun with hood open to let it completely dry out. You could have some vulnerable wiring spots or plug-in connections.

Zacharias · #5 05-03-2014, 01:34 PM

Hmmm.

Did you use a hose or a powerwasher?

Phillytwotank · #6 05-03-2014, 02:15 PM

Low pressure hose. More of a mist really near the electrical bits.

All other accessories seem to be working.

Come to think of it. I used to have to do that key jiggle trick on the old SD.

I'll have to try that this afternoon.

Zacharias · #7 05-03-2014, 02:29 PM

Quote:

Originally Posted by Phillytwotank

Come to think of it. I used to have to do that key jiggle trick on the old SD.

I'll have to try that this afternoon.

Okay, when you replied "negative" to my other post I thought you meant the key jiggle had not worked.

Logically if the stuff works on ACC but not in RUN, the problem sounds like a power supply issue, the engine wash is just a fluke of timing. I can't think of anything under the hood on these cars that would affect that.

sleepstar · #8 05-03-2014, 07:08 PM

could a problem with the resistor cause this? its the exposed wriggly wire/toaster looking thing on the passenger fender. if you soaked it good with water maybe that would cause a problem??

Zacharias · #9 05-04-2014, 04:08 AM

Quote:

Originally Posted by sleepstar

could a problem with the resistor cause this? its the exposed wriggly wire/toaster looking thing on the passenger fender. if you soaked it good with water maybe that would cause a problem??

Good call but how would that result in the blower running in the ACC position and not with the ignition in the RUN position?

Phillytwotank · #10 05-04-2014, 08:18 AM

So I went out yesterday. Left the driveway with the same symptoms I described.

Tried to start the ACC in every position. No joy

Tried the key jiggle. No joy

Drove around with the windows down for an hour or so be cause it was a supper nice day.

Left the car parked at my destination for a couple hours.

Hopped in to go home and tried the ACC again. JOY!

Everything back to normal.

So my problem seems to be solved but the cause is still a mystery.