MbNeedshelp

My 94 W140 stopped charging, the bat light was flickering I investigated and found wire loose then broke off completely from alternator. replace wire and now bat light is on steady and only getting 11.5 volts at battery. all fuses are ok. if its a relay I don't know where it is. I don't have a manual, I have tried to find one with no luck. also know most wires in the eng compartment are bear. the insulation have come off. Mercedes messed up there. please any help would be great.

optimusprime m1

If like the older alternators the regulator needs replacing .You should see the regulator brush box on the rear of altrnator .It only needs you to removing the electrical connector on the rear .Then remove 2 screws ,the regulator should lift out .Refiting is in reverse order.There must be a reason for the bad condition of your wires .If insulation is missing, i would say its been over heating to do this. Meaning a bad short .

optimusprime m1

You do need this part .You can replace the regulator .This is what it looks like but may be not the same number , i did look on ebay . So it might be the right one .You can see the number on the one you remove.

MbNeedshelp

Thanks for the help. about the missing insulation, I have read and seen on several other 94 W140 the same problem. MB used "Biodegradable" material that year which deteriorates over time leaving no insulation the wires . I need a new eng wire harness the part # is 1405402005, but MB stopped making them, so now what. I can purchase a new regulator, but I have no power to lead that broke. I believe it's the exciter for the alternator. Does the one wire to the alternator have a fuse or relay, if so where are they located ?

optimusprime m1

Mb i can see no relay to the alternator at the moment...I dont think anything goes to the alternator ,its for power comeing from it ..I will check out a diagram on wires .

MbNeedshelp

Thank you. Could you tell where I can get a wire of my own. I have purchased 3 service manuals on line that suck b_als !!!

optimusprime m1

Yes dont know why .This is the same on the 260e W124 as well. Heat as a lot to do with it. You are never going to sort it if the loom is split and shorting out .The looms cost over £500 in the uk .You could try pick and pull yard .


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optimusprime m1

You can get a download in pdf for a few bucks Google search is the best bet ..Put in the search box what you need .

jylee

A guy in New York rebuilt my S320 lower harness, I found him on peachparts.com. I didn't have time to rebuild, but most DIYer can rewire once the harnesss is removed.

anziani

If you haven't replaced your main wiring harness, you are "tilting at windmills". I haven't heard that new harnesses were not available. If true you might contact Victor at
vsandvs@optimum.net . (Think this is a current address) He is in the Brooklyn area and does great work at rebuilding/rewiring Throttle actuators. Do you not have an indie Benz mechanic in your area? That would be my first approach.
Anziani