Results 1 to 6 of 6

Thread: Driver power seat and telescoping steering wheel inoperable 1992 500E

  1. #1
    92 500E
    Join Date
    Dec 2012
    Location
    Toronto, Canada
    Age
    32
    Posts
    52

    Driver power seat and telescoping steering wheel inoperable 1992 500E

    Yet another issue that needs attention:

    The driver side power seat does not work at all. None of the function work.

    Also the power steering wheel..aka telescoping wheel adjustment is dead as well.

    I have done some reading, pointing to issue associated with the convenience module found underneath the driver seat.


    http://johnmeister.com/DieselBenz/TE...ay_control.pdf
    Pg 11:
    N32/1 Left front power seat control module

    I am wondering if these 2 convenience items (memory power seat driver and telescopic wheel) are linked together.

    So to start trouble shooting:

    1. Need to identify the Ground location on W124 chassis that are applicable to my issues:
    http://w124-zone.com/downloads/MB%20..._locations.pdf

    2. Check all fuses and modules that are working with system.

  2. #2
    92 500E
    Join Date
    Dec 2012
    Location
    Toronto, Canada
    Age
    32
    Posts
    52

    Re: Driver power seat and telescoping steering wheel inoperable 1992 500E

    Ok so checked and there is 12 V going to the seat module underneath the driver seat. \

    I again looked at the left side power seat memory switch. I took it apart. I did not found any dirt in it. Put it back and again,not a single function works.

    Side note: I took apart the passenger side switch since the seat back movement was intermittent but everything else worked fine such as fore and aft and up n down.
    Now the seat movement works as well.

    Me thinks the module is no good. Power gets there and does not come out...to the 3 motors.

    I removed the seat and tested the 3 motors with a 12V drill battery. All motors work fine and all movements happen .

    So now I am on a quest to find procedure to troubleshoot the module.

    I removed the module from the bottom of seat using a 7mm socket and u joint. Can also use a 7mm flat wrench.

    I looked at the boards and did not find any bad solder joints or conspicuous parts on the circuit boards.

    The search continues. I took some pictures will post later.
    Last edited by e300d; 02-18-2014 at 03:27 PM. Reason: added more info.

  3. #3
    92 500E
    Join Date
    Dec 2012
    Location
    Toronto, Canada
    Age
    32
    Posts
    52

    Re: Driver power seat and telescoping steering wheel inoperable 1992 500E

    So I pulled the module out and opened it up

    Found the board to be in good shape except for :

    That big 1.5 diode..has a little burn mark and some crap bubbling out of it







    Rest of the board looks ok. no loose joints etc...



    Part number of the driver side seat module of a 1992 500E with heated seats and memory seats for refrence:

  4. #4
    E500E Guru TerryA's Avatar
    Join Date
    Jul 2009
    Location
    Orange County, CA
    Age
    76
    Posts
    1,323

    Re: Driver power seat and telescoping steering wheel inoperable 1992 500E

    e300,

    I sure hope you checked the fuses before you removed all of that gear. I had the same problem. I removed all of the fuses in the fuse box and cleaned the contacts and it all worked again. If you haven't done it yet please do before you go out an buy a lot of parts you don't need.

    Good Luck
    Terry

  5. #5
    Site Honcho
    Klugscheisser
    Ich bekenne mich
    nicht schuldig.
    gerryvz's Avatar
    Join Date
    Nov 2008
    Location
    Annapolis, MD
    Posts
    17,954

    Re: Driver power seat and telescoping steering wheel inoperable 1992 500E

    Break out the soldering iron

  6. #6
    92 500E
    Join Date
    Dec 2012
    Location
    Toronto, Canada
    Age
    32
    Posts
    52

    Re: Driver power seat and telescoping steering wheel inoperable 1992 500E

    Soldering iron it is lol..

    Hi Terry, cleaned terminals and replaced all fuses to copper ones.

    Swapped around the K5 and K24 relays

    Checked for voltage at the fuses box. OK

    Removed and cleaned the seat switch

    Checked for voltage present at the red wire powering the control module under the driver seat. PN 129 820 0126


    I hope that little diode is what I need to replace.

    Cheers
    Sebastian

Similar Threads

  1. HOW-TO: Repair Inoperable Power Headrests
    By DerFuror in forum "HOW-TO" Tutorial Articles
    Replies: 32
    Last Post: 08-23-2015, 09:34 AM
  2. Repairing inoperable rear seats power headrests
    By 550Maranello in forum Interior Topics
    Replies: 6
    Last Post: 10-03-2012, 12:10 PM
  3. WTB: Euro/JDM Power Seat Module
    By T-500 in forum Wanted to Buy
    Replies: 1
    Last Post: 02-27-2011, 10:02 AM
  4. FS: 1992 500E steering wheel & airbag
    By gsxr in forum Parts for Sale
    Replies: 2
    Last Post: 04-19-2010, 10:15 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •