140 blower motor problem, Please help? - PeachParts Mercedes-Benz Forum

Davepnola · #1 09-08-2004, 01:42 AM

I am pretty sure the blower regulator is bad, but I would like to verify postively. I need to know what voltage I should be getting out of the small wires that go to the blower regulator.

Also this car is 93 300 se 140 body style.. Will the push button give you DTC codes for the AC. I tried the procedure for the 500 series but I did not get into DTC readout mode. I was able to hold rest button in auto mode and I think either # 6 or 8 I do not quite remember, but is was the reading for blower voltage or reading was 45 I think max was 60 if I was reading correct.

I just do not like to waste money and want to be 100% sure what is the problem ? Thanks in advance

Ps: also if it is the blower regulator, who has the best price? I think I found it on the net for 165.00 , but I thought I read someone here bought it from member for 135.00 or so........... Dave globalauto@yahoo.com 504-234-4458

mbdoc · #2 09-08-2004, 08:28 AM

The control voltage from the A/C pushbutton should be between 0.8V to 7.0V depending in selected blower speed.
The blower regulator is a HIGH rate failed part! MAKE sure to keep a fresh micro-filter in the car as they can cause blower failure when they get clogged.

oldsouth · #3 09-12-2004, 07:18 PM

I am having the same problem. Blower blows but not as hard as it did. Does not have a high speed anymore. There are two on the net. One does not specify brand and the other is a behr. Which one is the best?

stevebfl · #4 09-12-2004, 09:20 PM

The Behr one is a redesigned part that is probably a much better part. It is bigger and has much better heat disapation through a much larger base. The other one is an aftermarket source cloned on the original design. It would be lucky to be as good as the original high failure rate part.

We only use the Behr one. If I couldn't buy a Behr I would buy a complete Bosch motor as they are often part of the failure anyway and the motor comes with a new Bosch regulator. The complete motor with regulator can be had for not much more than the list price of the regulator.

oldsouth · #5 09-12-2004, 10:05 PM

Steve, what is the procedure to test voltage at the fan to make sure the problem is the regulator? What should the voltage be on high? 1995 S350 - 265,000 miles - fan or regulator never been touched.

Thanks!

stevebfl · #6 09-12-2004, 10:24 PM

Doc gave you the numbers on voltage. The yellow wire if I recall is the control circuit. hi blow will be around 7v, maybe only 6v.

I might consider a whole blower with that many miles. Remember the new blower comes with a regulator.

oldsouth · #7 09-12-2004, 10:33 PM

So test the yellow wire at the regulator for the stated voltage and if it is correct the problem is the regulator. Any way to test voltage at the fan itself to further test the regulator?

JimF · #8 09-13-2004, 11:14 AM

regulator is the problem by going to the Operational Check (OC) mode using the readout contained in the N22 module.

Go to my web page, select Menu#15 and after accessing the OC mode, select "8". Turn the blower speed control and you should see it go from min to max which corresponds to the MIN and MAX settings on the wheel. If you see that, then just replace the regulator. As everybody has stated, the regulator is a failure prone device.

oldsouth · #9 09-13-2004, 11:43 AM

Thanks! Value goes up to 60 on max. Will replace the regulator. Checking now to see if the fan motor only under the parts list includes the regulator.