[W126 Coupe] Strange instrument cluster behavior

[Axel Wulff]

Markus,

The later models have only one capacitor for the clock, just in case you 
found it confusing.

I've found it easier to swap the clock mechanism than to change the 
tachometer.

When you replace the capacitors, make sure you install them the right way 
(+, -). I didn't, screwed up the first clock and had to swap the whole clock 
mechanism.



Regards,
Axel J. Wulff
610-731-5453 Cellular
610-572-4611 Home






>From: Dick Spellman <spell.yy at verizon.net>

>Reply-To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

>To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

>Subject: Re: [W126 Coupe] Strange instrument cluster behavior

>Date: Sat, 15 Sep 2007 21:22:52 -0400

>

>Markus:

>

>The capacitors on the clocks just dry out with time.  So, replacing with 

>another clock will eventually result in the same dead clock scenario.

>

>Perhaps you can review this write-up and see if you want to tackle the 

>repair or just send the entire IC to a VDO repair outfit.

>

>Good luck,

>

>Dick

>

><http://web.mac.com/dakota/Mercedes/Projects_files/126_IC_CLockRepair_1.pdf>

>

>Markus Meyer wrote:

>>Well, the speedo pod must be the problem.  I took the original cluster 

>>now, switched JUST the speedo pod with another one, and everything worked. 

>>  So the common thread with problems appears to be the speedo pod, because 

>>with it, all other parts even when known to be working don't work right, 

>>but when a different speedo pod is in there, all other pods work ok (even 

>>the original ones).

>>  Now to figure out how to swap a known working clock with the bad one in 

>>my existing tach pod.....or to swap out just the tach and leave the good 

>>clock in another pod....but after removing screws the clock seems to be 

>>sodered in at the back, and the tach of course has 3 wires sodered in.  

>>Not sure what is easier to change out?

>>

>>Markus Meyer

>>mfm at meyerprobateproperties.com <mailto:mfm at meyerprobateproperties.com>

>>www.meyerprobateproperties.com <http://www.meyerprobateproperties.com/>

>>Meyer Probate & Properties, LLC

>>484-919-9762

>>

>>

>>     -------- Original Message --------

>>     Subject: Re: [W126 Coupe] Strange instrument cluster behavior

>>     From: Markus Meyer <mfm at meyerprobateproperties.com>

>>     Date: Sat, September 15, 2007 8:42 pm

>>     To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

>>

>>     Toasted the cluster you say - which part - just the speedo pod?  I

>>     found it strange that when I first swapped out only that one pod

>>     with oil/temp/gas/vacuum with a known working one, it also acted

>>     funny.  Then when I put the other complete cluster from the 560 in

>>     which was known to be working, everything worked fine (except of

>>     course tach and speedo are off).  I may try putting a good known

>>     working speedo cluster into my original cluster to reuse the "4

>>     pod" and tach pod to see if they are okay.  I'm just surprised I

>>     would have fried the speedo pod and nothing else, but so far thats

>>     wh at it looks like.  Guess with that damned clock not working I

>>     "forgot" that wire was hot dammit...I tested all the connections

>>     several times and looked for fried wires and the such before

>>     putting that complete known good cluster in and found nothing

>>     obvious, and no fuses blown, etc.

>>

>>     Markus Meyer

>>     m fm at meyerprobateproperties.com

>>     <mailto:mfm at meyerprobateproperties.com>

>>     www.meyerprobateproperties.com

>>     <http://www.meyerprobateproperties.com/>

>>     Meyer Probate & Properties, LLC

>>     484-919-9762

>>

>>

>>         -------- Original Message --------

>>         Subject: Re: [W126 Coupe] Strange instrument cluster behavior

>>         From: Dick Spellman <spell.yy at verizon.net>

>>         Date: Sat, September 15, 2007 8:13 pm

>>         To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

>>

>>         Whew. Marcus. That wire you pulled off of the lug on the clock

>>         module

>>         is 12 volts hot at all times. The spark you describe would

>>         have been

>>         making contact with the cluster backing which is a ground

>>         path. So

>>         that's a dead short brief as it may have been.

>>

>>         I'd go over everything one more time and see that the

>>         connections are

>>         correct. And be careful with that hot 12VDC lead. You may have

>>         toasted

>>         the cluster, not sure.

>>

>>         Dick

>>

>>         Markus Meyer wrote:

>>         > Hi guys,

>>         >

>>         > I have a question about the instrument cluster. I was taking

>>         the

>>         > cluster out to see about painting the needles. When taking

>>         the wire

>>         > off the clock it sparked because as I pulled it off I guess

>>         it touched

>>         > to the pin again. Anyhow, after putting it all back

>>         together, the

>>         > temperature/gas gauges were maxed out and the oil pressure was

>>         > minimized. And the dash lights would go out when I started

>>         the car,

>>         > go back on when I shut the car off.

>>         >

>>         > Now this is what gets weird. I then installed a known good

>>         working

>>         > cluster from another car. Everything worked fine. So now I was

>>         > totally confused. So I then swapped just the speedo pod from

>>         the

>>         > original cluster to the second cluster where everything worked.

>>         > Again, the strange behavior! Put the second speedo pod back

>>         in the

>>         > second cluster, everything fine.

>>         >

>>         > So....what happened? Why would the speedo cluster cause the

>>         > temp/gas/oil pressure/vacuum cluster to act funny? Is there

>>         a fuse I

>>         > blew somewhere I can' t find/see.

>>         >

>>         > And I can't just use this second cluster as is because one

>>         is for a 6

>>         > cylinder and the other is for an 8 cylinder and the speedos

>>         and tachs

>>         > are calibrated differently. I just want to make sure I

>>         didn't mess

>>         > something else up somewhere I'm not aware of...

>>         >

>>         > Thanks,

>>         >

>>         > Markus Meyer

>>         > mfm at meyerprobateproperties.com

>>         

>><http://email.secureserver.net/pcompose.php?aEmlPart=0&type=reply&folder=INBOX&uid=2206#Compose>

>>         <mailto:mfm at meyerprobateproperties.com

>>         

>><http://email.secureserver.net/pcompose.php?aEmlPart=0&type=reply&folder=INBOX&uid=2206#Compose>>

>>         > www.meyerp robateproperties.com

>>         <http://www.meyerprobateproperties%0A%20.com/>

>>         <http://www.meyerprobateproperties.com/>

>>         > Meyer Probate & Properties, LLC

>>         > 484-919-9762

>>         >

>>

>

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