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W124 electric meltdown

Discussion in 'Electrics, Vacuum, Ignition and ECU' started by lanciaman, Nov 23, 2012.

  1. lanciaman

    lanciaman Senior Member

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    Location:
    Aberdeenshire
    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Well not really but my tame mechanic was looking at why the interior light wouldn't work - seems the unit needs replaced. However, went to take the car this morning and none of the electrics now work, or at least the one's I tried in the 30 seconds before I gave up and took the other car.

    No power windows, no wiper function, no electric seat function. Lights and radio worked and the car started fine.

    Any idea what common factor connects these non working electrics?

    thanks
     
  2. grober

    grober Senior Member

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    Location:
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    Your Mercedes:
    W204 C200cdi estate
    SOUNDS AS IF THE FUSE TO THE CONVENIENCE CONTROL RELAY HAS BLOWN = FUSE C 16amp in the main fuse box-- if its not that then check the other fuses--- your vehicle " electrician" did isolate the circuit he was working on of course. :Oops:
     
  3. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Thanks for that. Oh I'm sure he did.......

    :rolleyes:

    Will have a check tomorrow.
    cheers
     
  4. OP
    lanciaman

    lanciaman Senior Member

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    Aberdeenshire
    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Took a quick look but not fuse C. Or any others by the look of it. No power windows, roof, wipers, seats, seat belt presenter. Then after fiddling with fuse 2, window worked down - wouldn't go back up, seat moved and nothing else. Opened the door and the drivers window worked again too go up. Then got too dark.

    Couple of the fuses refer to terminal 86 in the manual. What is terminal 86 does anyone know?

    thanks
     
  5. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Trying to research this- could it be the ignition barrel/switch? It is quite loose. How can it be checked?

    thanks
     
  6. grober

    grober Senior Member

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    Your Mercedes:
    W204 C200cdi estate
    You might have a problem with the convenience relay K24 which feeds power to the convenience control unit via fuses G and H Try giving it a tap or reseating it---- its in the relay box behind the fuse box.
     
  7. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    thanks Graeme -will have a look in the morning
     
  8. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994

    One thing niggling - I can see the comfort/convenience relay could be the issue but would that affect the wipers (and no flash for headlamps)? Indicators work - but need to test hazards....

    A puzzle...
     
  9. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Well, given that a try but no joy. Checked the unit under the rear seat to see if anything loose, but all tight.... so, a bit stumped.

    300CE 24 breaking for spares anyone??!! :D
     
  10. Bolide

    Bolide Senior Member

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    Your Mercedes:
    BMW 525 Diesel Touring
    Sounds like corroded fuses & fuseholder to me

    Nick Froome
     
  11. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    It doesn't look particularly bad. But why would all these things go at once - wipers, windows, sunroof, electric seats - and others not? What links them?

    Surely the wipers are not part of the convenience module?
     
  12. d215yq

    d215yq Senior Member

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    Your Mercedes:
    1987 W124 300D 280k miles
    When my satnav short circuited the cigarette lighter the windows and roof did not work, unless the door was opened. Didn't try/don't have the otther equipment you have but replacing whatever fuse feeds the cigarette lighter (IIRC number 2?) solved the problem
     
  13. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Interesting. It seems odd it happens immediately after testing the interior courtesy light and swapping the window switches over to test the passenger window - could be coincidence but odds are something has happened there. Need to check every fuse very carefully I guess but I don't understand it!!

    thanks for the tip
     
  14. huey

    huey Senior Member

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    Your Mercedes:
    W203 cdi 2004 Estate
    It might be a good idea to remove all the fuse's one by one and clean the contacts with non drying contact cleaner (from maplin), they do corrode over time.
     
  15. OP
    lanciaman

    lanciaman Senior Member

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    Thanks Mark. Agreed - but it must be more than that - why so many things fail at once? These functions must be linked by something - at least that is what my brain (befuddled) is telling me.

    But they will need cleaned regardless..

    cheers
     
  16. syncropaddy

    syncropaddy Senior Member

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    .... too many cars!
    It could be the fuse box itself. One of the things I did on my preventative maintenance list was to clean each fuse location and replace each fuse with a new one. I hate those fuses that MB used back then
     
  17. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    Thanks Andrew. That is the first step I think. Have ordered 100 of the crappy fuses!! Then at least if that is done and doesn't work, we have ruled it out cheaply!!

    cheers
    Lindsay
     
  18. OP
    lanciaman

    lanciaman Senior Member

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    Your Mercedes:
    E220 Cabrio (A124) - 1994
    An update. It was indeed the fuses. Cleaned them (still waiting for the new ones) and bingo - all working again. :D

    Thanks to all who responded.
     
  19. Woody121

    Woody121 Active Member

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    Hi - I thought it worth posting that I've solved my meltdown issues by simply checking the seating of every fuse in the fuse box, presumably as a result of condensation and oxidation jiggering up the contact on them.

    A nice new battery (despite what a roadside breakdown expert concluded about the life of the old one) has worked absolute wonders for the rough idling problem I'd been plagued with. Always test the ability of the battery to supply under load and if in doubt change it!

    Woody
     

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