OK the ac compressor locked up now I can't run the heater, every time It is turned on the belt is squealing. so I cut the belt and now I can't get the blower motors to come on. Need some one to pass on a wiring diagram so I can trace this out and see what I need to jumper so the heater will work thanks JNT

have you checked ALL the fuses? the 30amp one outside the fuse box? the fuse for the compressor inside the fuse box etc. hopefully it didn't take out the pushbutton module.

__________________
R Martin
Dallas, TX (Addison)

86 560SEL, 128K

Heat should work fine in ECON (first button to the left of the off button on the ACC control) without trying to operate the air conditioning compressor. At least, that's the way my '86 works.
I'm working onmy heat now, see my next post for details, Hope this helps you.

thanks, I know about the fuses and the ecom button, the kids are using it that way now. I was just trying to figure out how I could run the heat with out the ac. if you unhook the compressor at the clutch it will not let the motors under the dash blow, so I hooked up the clutch and cut the belt off and still do not have blowers. the red fuse is good but I am not familiar with this thirty amp fuse you spoke of.

Blower fuse is an in-line type, mounted on the "fake" firewall in front of the brake booster area.

The a/c compressor has NO effect on heater operation.

__________________
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thank you Doc, I was very confused, so then I must have a fuse that is out I did find a fuse blown in the fuse box I think it was # 5 I will look for an in line fuse. JNT

Hi Doc, I took another look at my 420 sel 1990 model,and did not see what i would call an inline fuse, took some pictures perhaps you could point it out thanks JNT.

Attached Thumbnails

     

i have an 86 560sel.. my inline fuse is right in front of the fuse box... looks like it was added on..

on you pics...what is in the square black box just behind the fake firewall?

i've heard some later models have a 30 amp fuse that looks like a strip of metal. perhaps it's in that little black box?

__________________
R Martin
Dallas, TX (Addison)

86 560SEL, 128K

The black box is the fuse box it has the thirty amp fuse marked #5 posistion for the heaters Red fuse.

The "little" black box fuse holder in all of those pictures are of the blower motor fuse holder.

Fuse # 5 in the box is power for the a/c pushbutton.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Thank you Doc, I just was not sure, thought I would ask before I did something I should not do. JNT