[khomer2]

I have led bulbs in my 02 ML.
Had to dim them down; they were so bright bleeding across the display.

Check the simple stuff first:

Loose connector behind the cluster?,

Leds, I recall some or all have polarity, so they may need to be reversed?
Make sure the contacts are good, on those little connectors.

 

[Newby.ben]

I have led bulbs in my 02 ML.
Had to dim them down; they were so bright bleeding across the display.

Check the simple stuff first:

Loose connector behind the cluster?,

Leds, I recall some or all have polarity, so they may need to be reversed?
Make sure the contacts are good, on those little connectors.

Thanks for the advice. I have checked all those and have found that there is no power only on the board where those three bulbs insert. I’m trying to figure out where that power is supposed to come from.

 

[ed7c9]

Thanks for the advice. I have checked all those and have found that there is no power only on the board where those three bulbs insert. I’m trying to figure out where that power is supposed to come from.

Did you try installing the old bulbs and seeing if you still have the same issues?

 

[Newby.ben]

I have led bulbs in my 02 ML.
Had to dim them down; they were so bright bleeding across the display.

Check the simple stuff first:

Loose connector behind the cluster?,

Leds, I recall some or all have polarity, so they may need to be reversed?
Make sure the contacts are good, on those little connectors.

Thanks for the advice. I have checked all those and have found that there is no power only on the board where those three bulbs insert. I’m trying to figure out wh

Did you try installing the old bulbs and seeing if you still have the same issues?

Yes. Same issue.

 

[khomer2]

If I recall, there is 1 maybe 2 locktype connectors that connect to the backside of the instrument cluster. Not sure which lead is power, but do check that all the pins are not bent and that they go in straight, into their proper pin hole for a proper connection.

 

[ed7c9]

Might also want to use the same LED's that @khomer2 used on his car...I admit I dig the look of yours ...I need to replace a bulb in my cluster but I don't want to use LED bc of this reason (potential issues). I ran LED's in the overhead light on my ML55 and ran into all kinds of goofy issues.

 

[Newby.ben]

Did you try installing the old bulbs and seeing if you still have the same issues?

I put in all original bulbs and the problem is still there.

 

[khomer2]

A view of the backside of the cluster.
Are you sure the connector is properly connected?
With the bulbs, are you sure the bulb housing (twist sockets) that are not lighting up, are fully twisted/turned, for the contacts to make proper contact onto the terminal contact points on the backside of the cluster?
Try using some electrical contact cleaner (like deoxit or similar) on the contacts to make a proper connection

 

[Newby.ben]

So, if anyone on here understands wiring diagrams and circuitry, let me know if I’m on a possible right track.
First picture is the wiring diagram for the cluster. I think the circled part is the three lights in question. These three lights (second picture) turn on and off differently than the rest of the cluster and is powered directly from the battery through a power transistor (third picture). I am thinking of unsoldering this pt to see if it defective. I’m waiting on some pt I purchased so I can see if there Is a difference in the two. Is my understanding of the diagrams correct?