LEDs as Instrument/dash lights in 123 series - Page 2 - PeachParts Mercedes-Benz Forum

Chad300tdt · #16 10-12-2007, 01:36 AM

Here is a picture of the cluster with the 194 LED bulbs installed. It's blurry because I took the shot without a flash. I took this in my garage with the lights out except for the headlights and cluster. You can see that all parts of the cluster are clearly visible.

funola · #17 10-12-2007, 07:12 AM

Thanks for the pic Chad. I wonder if it's gonna be too bright with the LEDs since my dimmer is bypassed. I have no complaints of the cluster lighting except for not being able to read the odometer and trip meter clearly at night. I was thinking of adding a bulb or LED behind the faceplate to light up the digital wheel counters. Don't know how well that would work. Anyone tried that?

Gil · #18 10-12-2007, 10:31 AM

Quote:

Originally Posted by Chad300tdt

I tried the 74 Wedge base LEDs in the CCU and wasn't impressed. I think the standard bulbs are better suited for that application. The LEDs ended up looking half as bright as the standard bulbs.

I haven't tried to dim the LED in the cluster, but if it doesn't dim who cares? The reason I want LEDs is so I can have my dash as bright as possible. There is never an occasion where I would want them dimmer.

So you just went with the stock bulbs in the CCU? I was hoping to avoid that (can't stand melting parts

)

viggen9 · #19 10-12-2007, 10:36 AM

Quote:

Originally Posted by Chad300tdt

Here is a picture of the cluster with the 194 LED bulbs installed. It's blurry because I took the shot without a flash. I took this in my garage with the lights out except for the headlights and cluster. You can see that all parts of the cluster are clearly visible.

How do you access the bulb sockets? Remove Instrument cluster first?

Chad300tdt · #20 10-12-2007, 10:54 AM

The stock bulbs for the CCU are 2721. They shouldn't be hot enough to melt anything. The 74 Wedge Base LEDs are OK but they don't really fit properly into the snap in socket on the CCU. They fit bulb socket fine, the head of the LED doesn't fit completely in the rear of the CCU or the fiber optic spider. IIRC the LEDs only fit into the socket behind the temp wheel in the CCU, nothing else.

As for the Guage Cluster. You need to remove it first. If you take out the under dash panel, you can reach up behind the cluster and push it out from behind. There is a rubber belt around the cluster that holds it in place with friction. You can access the bulbs without disconnecting all the wires from the cluster. Just pull it out as far as it will go toward the steering wheel. You will see two plastic tunnels on the top of the cluster. The bulbs are on the back of the cluster lined up with these. You need to untwist the bulb base from the cluster and pull it out. Then you can pull the bulb from the twist base. If the bulb breaks while pulling it out like mine did, you can chew the glass out with a needle nose. The LEDs fit snugly and you need to test that they are in correctly before putting the cluster back in the dash. The LEDs are polarized and only work when oriented in the socket correctly.
Also be sure to use Dielectric Grease on all contacts. It ensures you have the best contact possible which gives the max brightness.

You can make tools to remove the cluster using a metal coat hangar, but I think it is easier on the dash and cluster to push it out from behind. If your cluster has never been removed, it may take a little force to get it out. After the first removal it comes out easier.