Starting a couple of days ago, the turn signals and the outside temp guage stopped working. I checked all fuses and they all are OK. I know these cars had wiring harness problems, but these are the only problems with the whole car. Is there anyplace I should start to look first? Any help will be greatly appreciated...

Its possible that the two problems are unrelated and happened coincidentally.

A few things I would check for the turn signals:

1. Do the 4-way flashers (hazards) work? (are the bulbs bad?)
2. Does the windshield wiper work?
3. Does the brights switch work? (with #2 - is the combination switch bad?)
4. Do the brake lights come on? (is the combination relay bad?)

About the temp display - does it display anything at all or just blank (or is the LCD completely black)?

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Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE

The hazard flasher works fine. The windshield wipers work fine too. The temp guage either is very faint or not visible at all. Prior to this, it worked fine. I have not checked the brake lights yet. My main concern is the wiring harness, which I thought was already replaced on my car. Is there a relay that has both the turn signals and temp guage on it? Thanks again

Does the horn work?

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95 E320 Cabriolet, 159K

Horn works, but is very faint, I reckecked and replaced all of my fuses today, and voila the temp guage workds, and the turn signals work. Had a couple of really old fuses in there. The horn is still faint though.....

I asked because I had a short in my horn that blew a fuse, which also served my turn signals.

I wonder if your faint horn may have a short and be blowing fuses. Check the resistance. My good horn was 0.8Ω. My bad horn was 0.2Ω.

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95 E320 Cabriolet, 159K