W126 Heater Blower
 

About a month ago, the heater blower in my '87 560SEL stopped working although all other functions of the climate control system appear to be working fine. Given the current cold weather and the more frequent need for defrost, this is not something I can go without for very long.

From reviewing posts here and the FSM, it appear that there are three possible problems: bad blower, bad contacts at the switches/buttons, or the blower control module. Is one of these generally more common than the others?

Thanks
jlc

What does the fuse and fuse block look like? I ask because of the possibility the fuse has blown, or overheated and burned the surrounding fuse block.

OF course the first thing to check is power supply, ie; fuse & power to the blower housing. IF that checks out the most common failure is the motor itself.

If the fuse continues to blow there is a retro fit kit made by MB that moves the fuse out of the fuse box onto the fender well and raises the current level. This is a common problem on the W126 as they age. The kit can't be used on other models or it could case a fire :eek:

It is very easy to replace the blower motor (if you are a contortionist).

If everything else checks out and you suspect it is the motor itself you can always set the fan speed to high and then bang on the area near the motor. Most times (if it is the motor) it will come on which means it needs to be replaced - a really untechnical way of checking but gets the job done.

if it starts with the bang method, it could be brushes which are replaceable. I did my 126 300SD in about 45 minutes
I never knew the fan had that much power. The brushes made a world of difference

Thanks for all the good info. :)

I checked the fuse first thing and it appeared fine. There are also a couple of other items, I've forgetten what, that run off the same circuit and they were still working. I haven't yet tried to trace the wiring and actually check for power at the blower as I haven't retested my ability as a contortionist. Any advice on how best to access the blower while minimizing the need to visit the chiropractor afterwards? :eek:

jlc

Put the passenger seat all the way back and be sure to put something thick and padded over the rocker panel so it won't kill your back while you are peering up under the dash. An old pillow actually works very well.
I am guessing it is the brushes as mentioned in the other thread. It is an easy DIY job if you have the patience and some Tylenol P.M.(or some form of "liquid pain killer" :D ).