I feel like there used to be a more specific sub-category for W123 vehicles, but things might have changed around here, so anyway...

Selling my old 300D to a friend. Took apart the center console to try to get some lights working behind the HVAC switches, etc. Pulled some fuses as well. Then it sat for a month. Came back, put things back together, and now the turn signal doesn't respond at all. It always worked fine before.

I checked all the fuses for continuity with a multi-meter, and checked them after they were installed - all work

I took a look at the relay under the ashtray, it was plugged in. It would be odd for it to fail, since everything worked before other things were taken apart.

There are a couple of plugs that we cannot seem to find homes for, so I don't know if they are related?

The first is a pair, one has a black head, the other a white head. Both have a flat metal tab and a single metal prong, shown in the first pic below.

The other, which I thought went to the cigarette lighter, though I can't find where it plugs in, is a white plastic plug shown in the second pic.

If anyone has any pictorials of how to trace the turn signal issue, it would be much appreciated!

Attached Thumbnails

   

Black head and white head go to the factory radio. They go from the dash to the fader and then get distributed fore/aft. They say L and R on the back.

The square connector IS for the cigarette lighter AND the factory radio harness. They use the same connector. Look on the back of your ashtray.

Do your hazards work? I believe the signals get routed through there.

FYI: lights behind the HVAC switches are either bulbs on the HVAC CCU, or fiber optic off the octopus. If they don't work, it might be your rheostat or your cluster lights are simply turned all the way down.

I agree 100 percent with YAK. Those are radio and cigarette lighter wires.

But... if the emergency flashers do not work, then turn signals will not work.

The turn signal flasher is in the emergency flasher.

__________________
80 300D 340K Owned 30 yrs
83 300SD 440K Owned 9 yrs - Daily Driver 150mi/day
02 Z71 Suburban 117,000
15 Toyota Prius 2600 miles
00 Harley Sportster 24k
09 Yamaha R6
03 Ninja 250

If you have to get at the turn signal relay it's right in front of the shifter, you have to take the wood off to access I believe. Maybe you knocked it loose somehow?

I've replaced mine before when I thought i was going crazy looking at all the bulbs for a blown one. Turned out the relay went bad somehow...new one in = no more fast blinkers for me

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1983 300TD - 202k with 5 speed Getrag conversion

+1 to all posts above; however I don't believe the red/black plugs are OE, though still probably for the radio.

Also, check the hazard switch to make sure it is in the "off" position. If somewheres between on and off the signals act up.

__________________
1982 240 D, 308,000 - 321,127 miles (sold)
1982 300 TD,166,500 - 226,000 miles
1998 E 320, 120,000 - 144,000 miles
2005 C 230 K, 26,000 - 77,000 miles (sold)

You have the 4 way flasher switch turned on. Turn it off.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Yep. Hazard switch failure, IIRC can kill both blinkers and flashers. You can take it apart and clean it up a few times to make it work, but you'll end up buying new. Searching at length will get you the part for a less than heart stopping price.

__________________
CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

Looks like a later car with separate switch/relay for the flashers, no?

Jay

__________________
On the road, currently:
'83 300D (German spec.) 168k mi. - - Wolfgang (tucked snugly away for the winter!)
'87 300D 375k mi. - finally went over to "The Dark Side"
'87 300TD 225k mi.
Cannondale 66cm CAAD5 w/Campy/Jamis Aurora
Hujsak Custom Fixie/Landshark Track Shark Custom/Ahearne Custom 29'er