Custom Instrument Cluster for 1992-1994/6 Benzes?
 

Hello all,

Recently my 1992 W140 instrument cluster died and I was forced to repair it. It was very challenging, but I did it. I learned that the Siemens VDO circuit boards were flakey and as a result there were recalls on all W140 clusters from 1992-1994. Perhaps other models are affected.

Unfortunately MB will no longer honour this recall even if yours fails, like mine. And you have little choice but to shell out $1500CA for a 'new' one or $600CA for a scrap yard one. Both alternatives will leave you with an incorrect odometer setting. MB sold just replacement circuit board in the early nineties, but eventually they decided it would be better to sell you the whole unit at full price.

Aaaanyways, there are only a few companies like Programa in Boca raton Florida who will service your cluster for $400US, I believe. I have a better idea. In the face of a poor aftermarket for the W140 and everyone trying to rip you off left right and center, i am proposing a new business idea.

Would anyone be interested in getting a custom instrument guage cluster for their Benz, 1992-1994/6? I can build a standard/custom one with cool indiglo lights made from top quality aftermarket guages like Autometer, and a brand new circuit board with 2004 IC technology, vastly superior to the crap that VDO made. I can also guarantee my work by honouring a long term warranty.

This would mainly be for the W140, but if I R&D further I bet I can make it work for all early ninety benz models. I can, of course, offer a standard repair service less expensive than anyone else, if you just want to repair your old cluster. And it wont be a kludge, it will be the correct fix to a bad VDO design.

Let me know if you are interested or just what you think of the idea. Unfortunately good guages are expensive so Id price the custom cluster between $1000 and certainly less than the $1500 dealer price. Currently I have not done this, but if the response is right, I can begin R&D and offer this service in the near future.

Necessity is the mother of invention, and my car has certainly given me enough need to break the monopoly that MB has on the options for an owner. I have a whole bunch of modification ideas for the early W140s. I am based in Toronto, Canada.

Thanks for your time!
E-mail at JimmiBenz@chargerr.com or respond here.

Look on Ebay. I saw some there last week.

Cheers,
Steve

What did you find to be the problem with the Cluster. Mine blinks on and off depending on the severity of ths bumps I hit. Most times it works perfectly.
:confused:

Well the problem with a used piece is that it could potentially be the same as what you already have, which is a recalled component. Only it hasn't blown yet.

Im not one to go out of my way to save a couple bucks. I dont mind paying $$$ if I really get what I need. Problem is that the VDO circuit boards are just poorly designed. The basic problem is, obsolete components (not used by anyone else in the biz) failing, and some pseudo ASIC chips, one that also failed, but have no specs. They have no specs because VDO does not like other people touching their things. So they hyper-obfuscate the design to corner the repair market. But if you have a lot of patients you can win.

We all have come to the realisation, over the course of ownership of these cars, that dealer parts are marked up 200% more than what they should be. This is just another example of the illusion of quality solely due to a brand name. I can do it better.

Frankly though, due to the underwhelming response here :) and in another newsgroup, it doesnt seem like it has the payoff.

Anyhow, like insurance, you dont really think about until the time comes when you need it.

Sorry N. Hodges, I forgot to respond in my previous message.

Your problem is most likely a ground issue. MB thought it was a good idea to connect a hundred ground wires to one bolt behind the instrument cluster, tied together with one locking-type screw. Needless to say, some W140s have bouncing ground issues. Mine was OK, but you will have to check yours.

It flashes because power has temporarily floated, which forces the microprocessor in to an unknown or reset state. That flashing is the chip completing a POST. Try it with your seat belt off and you should see the friendly seat belt warning flash a few times.

Remove the instrument cluster using two hand-held hook tools from your local HW store. Yes, there are no screws holding the cluster in. Make sure to lower the steering wheel down and forwards all the way and that the ignition is off. There are two hook type plugs, which you'll need the hook tool again to pry off, and two wierd round plugs. (I assume you have a W140) Once you remove them you can pull aside the cluster and investigate the now empty cavity. If the ground is OK, it could alternatively be a bad input or a bad component on the board.... in which case you can call me :rolleyes: !
but yeah, electrical problems, esp. intermittent ones, are tough ones.

Thanks. I will check out the ground issue today.

To remove a stuck cluster, try this
 

If you try to remove an instrument cluster that has never been out then the hooks can leave you frustrated or damaging your cluster. There is an alternative method to the removal. This is to remove the left side HVAC outlet and duct assembly along with the hose attached to it. By doing this one can put their hand in behind the cluster and push it out without doing any damage. Been there and done it as I had to send my cluster to Programa for repair of the warning lights flashing with either the wipers or turn signals on. I just filled the car with gas and drove it while the cluster was out for repair, no problem!

Tobias MB
3 MBs

What Did It Cost To Send Off To Get Fixed.

...And who, what, where is "Programa." Details please.

ProgRama info.
 

ProgRama is a Florida based instrument repair facility that fixed mine about 5 years ago for around $300, if I remember correctly.
They can be reached at www.programatools.com or 1-800-668-8843.
Their other business designs and manufactures scan and reset tools which are for sale.

Good luck...the 140 is the most troublesome model MB ever built!!

Tobias MB
3 MBs

Thanks for the info.

You are so right about the Mercedes(w140) being one of the most troublesome cars ever. :mad: :mad: :mad: :mad:

You know, I would love to know how Programa has figured out this circuit board.
I have tried contacting Siemens VDO, and they've told me to f!@#k off in not so many words.

That circuit board is amazing. Believe it or not theres an NEC 4-bit microprocessor on board. It actually takes in a voltage, passes it through a ADC, then to the NEC, then does some sort of calculation before converting it back to analog, splitting it up into 4 seperate signals, each representing 1 of 4 quadrants of the guage. All quadrants are ground to Vdd, except the first which is Vdd to ground. And then drive the guages in 4 stages.

And American guages have one wire. Hmmmmmm...

There are severall different voltage sources, mixtures of analog and digital signals, redundant circuits, transistors as amplifiers and transistors as switches. Obsolete components, components working in their breakdown regions.

I can guarentee you that they have not figured out this board on their own. Either they have a contrract with VDO and have a copy of the schematics, have found a cache of new boards somewhere, or plain made up their own boards. I believe the latter one...because its also my idea! :D

Tobias would you be willing to take yours apart for a little photo? I am consumed with curiosity!