INSTRUMENT CLUSTER

 

ISSUE:

Clock LCD display does not work - fading pixels

Gear selector does not work - fading pixels

Typical issue with these years Benzes

 

POSSIBLE SOLUTIONS:

 

1. Buy  2nd hand instrument cluster - I don't know if this will be straight swap or if you need coding, millage correction etc. I have seen one on Ebay for €40 plus delivery

 

2. Send instrument cluster to repair shop. You are talking about 2 x €20 for shipping plus whatever the man is charging. We say €50 for the argument sake. You are down €90 and probably 2 weeks without cluster and ability to start the car - I assume as I have not tried to connect battery with the cluster out.

 

3. Take out instrument cluster and do it yourself - obviously this is what I have done.

 

Tools needed:

Angled ring spanner 10mm to disconnect the battery

Torx/flathead/Phillips screwdrivers (don't remember exactly just check the video)

Hooks to remove cluster - you can make your own ones or buy the proper tool. I made my own but I do recommend getting the proper job. You can find them for about €15 delivered on ebay

Soldering station - yes station with temperature control not cheap soldering iron

T-Tip for soldering iron so that you can attach ribbon to PCB with the one blast

New PCB ribbons - you can try without new ones but take my advice and order new one it will save you a time later on

Acetone/Methanol/Isopropanol - or any other alcohol to clean PCB

Scisors, tweezers etc

 

Job description:

-Disconnect the battery - it's under the rear bench. There are two latches at each corner of the seat

-Remove the instrument cluster - this is tricky as hell when you don't have proper tool

-Open the enclosure

Option 1 - try to compress the existing ribbon with piece of credit card at the main PCB where the ribbon is connected. I did that initially and it fixed the problem for about the week. One section of gear selector faded afterwards.

Option 2 - remove old ribbons and solder new ones. If you never done this before experiment with some old electronics first as I guarantee you be buying new instrument cluster.

-Before you put everything back take the cluster half assembled to the car and test, test, test.

- when you put back the needles put them as lightly as possible - don't jam them too hard as the tend to stick to back plate and you will have a false readings.

 

Work time:

As I did everything twice. All together 6-8hrs of work.

 

Cost:

I only had to buy ribbons €5 - and T-Tip €10

If you need soldering station you can get one for about €100. I bought mine years ago and it payed for itself many times already

 

Conclusion:

Is it worth repairing ?- definitely YES.  As much as gear selector is not a must  the temperature and the clock are definitely on my priority list

If I was doing it again I would give it a try with 2nd hand instrument cluster. If that option works you are saving yourself a lot of work.

My advice here is: Buy set of hooks, take out instrument cluster, replace it with spare unit and put the stuff back. If you are successful let me know and I will post it on here.

 

Added 6 months after the repair:

I must press the needles too hard when reinstalling them. Fuel gauge from time to time would not go all the way up to the position. Had to remove cluster, open the cover and loosen the needle so that it was free to move again.