I have a sneaking suspicion that with this, you have crossed the threshold into starting a new business. You might not be aware of this yet.

You have now:
1) fixed the LCD temp readout, a perenially malfunctioning item in almost all the older MBs still on the road
2) fixed the cruise amp, another common problem

Not only have you successfully repaired these items you have shown the rest of us how. It doesn't seem like it's particle physics either! Brilliant!

There used to be a guy on the left coast who did this stuff, General Development Labs. I don't know if he does it anymore, who knows. At any rate, this kind of repair is in demand.

Next, you should try to figure out the CCU pushbutton unit! There's one for you. Although a common pattern I'm seeing is that it's those caps giving up the ghost every time.

You should throw a simple web page up and advertise repair services for this stuff. I'm sure there are a lot of units out there needing some similar repair across all makes of European autos. The electronics in these cars are ridiculously primitive, for a modern electrical engineer a cakewalk. Most people would sooner buy a rebuilt unit than replace individual components on the PCB.

I'd take you up on your offer to fix, but I've been lucky that my cruise amps have remained operational. I will however use your information to repair my LCD temperature readout. I like to solder too.

__________________
'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

HVAC push button repair on Gen. I W126 would be awesome.

I bought a new one 5-6 years ago and it broke just recently. If I press the middle or second from the right button, the fan doesn't kick on. I've got to press the fourth from the left button to get the fan to kick on and then click EC or the middle button if I desire those settings.

Based on what I've read on the forums this is a common problem with the units. I got a few from the yard to try out and they all exhibited the same problem!

I've tried soldering numerous times on two different units with no success.

__________________
1984 300 SD 384,000 Miles