Rszarka

Hi everyone

I am new here but hope to be visiting a lot now that I have found this place !
I have recently moved in with my aunt and she has a 2001 Mercedes Kompressor w203 and she comes to me whenever she has a problem as I am handy with things …so my questions are not actually for me but to help my aunt fix things on her car ! I am more of a motorbike kind of person, have BMW as my main transport …similar style as Mercedes but in bike form haha
I apologise for joining the forum just now and immediately asking a question in hopes I can help Liza out

so 2 days ago she had a flat tire ..and I helped her put her spare on ..yeah was kind of a neat system with a deflated tire and a compressor that went into her cigarette lighter or appliance port .
well we inflated the tire then my uncle rather carelessly pulled the compressor plug out and it yanked the entire cigarette lighter port out …since then it has not worked for her !

so the first thing I did was check the blue 15 amp fuse that’s in the front under the bonnet fuse #47 …it is fine no problems there ..
so power is getting to the actual unit as the little light bulb that is attached to that plastic retaining ring comes on …used a multi meter and 12.3 v coming in …it’s the bottom prong on the plug and a small gauge blue and white wire….

when I tested inside the lighter unit itself I found 0 volts coming in ..

I then pulled off the actual lighter unit from the wiring …used the multimeter in continuity mode and found proper circuits from all the prongs …so it’s obvious that the actual unit yiu plug the utility into is all working ….

‘’so there is a black and yellow wire on the top left prong of the plug …which is neutral ground I assume ..

‘’then the top right prong is a brown wire and that I again assumed would be th elite power wire in that should hold 12.3 v ..

the brown wire has a small nick in it where the wiring is exposed …but the wire is not broken …found a ground point and tested the brown wire at the male end of the plug and yeah 0 bolts coming through that brown wire ..
so replacing the cigarette lighter would not help! It seems that when my uncle yanked out the plug something has happened to that brown wire the live wire ..on the end not connected to the cigarette lighter utility plug ..

any ideas guys where that wire originates ? I do not have the service manual for this car as yeah it’s not even my car haha
would anyone here have any ideas what I could check or how to find why the live wire has no power ?

the fuse is good I’m sure of it as I have 12 v coming to the bottom prong of the male plug …I thought of jumping the power across from the light bulb wire ..blue and white to supply 12 v to the brown wire but that’s a bad idea as the blue wire is a small gauge wire as it Carrie’s very little load ..while the utility plug live wire is a much heavier gauge wire as it Carrie’s substantial load …so won’t be doing that! It’s a Jimmy rig at best and not a good idea.
so yeah would anyone happen to have any ideas? Or a wiring diagram form the utility plug / cigarette lighter ? Maybe when my uncle yanked it out her tore off the originating end of the live wire …tyere is visible damage to it up near the plug …

‘The utility plug would not be on a relay that could have blown right ? I mean why would it be on a relay..I would just assume power is directed without interruption through the fuse and to the plug as soon as you turn on the ignition key..
I just know if my aunt takes this to an electrician she will pay at least a hundreds bucks for a 5 min job hahha

thank you so much in advance to anyone that may be able to help with some advice on how to fix this or wiring diagrams!

cheers
robert

navari

Check relay M in engine compartment , this pdf for w203 EU version