1984 300D
Emergency blinkers mean: When you use the turn signal (left or right) the "4 way flasher" come on.

New flasher relay installed.
New emergency rocker switch installed.
All new fuses (ceramic)


Does anyone have suggestion to fix this?

Nick

Have you done anything with the control stalk?

Check your turn signal stalk switch aka combination switch.

I have 1983 240D, pin numbers are for that car, I believe yours is the same. Someone correct me if I am wrong...

Open lower dash cover locate C106 (connector for stalk switch) and unplug.
Take a jumper wire and jump pin 7 to 6, on the connector side leading to the car harness, away from switch, you should get left blinkers only.
Then try 7 to 8, that should get right blinkers.
If that passes then use continuity tester on switch side of C106, no continuity between any 2 of pins 6, 7, or 8 with switch in neutral position. With switch set for left turn, only pins 7 to 6 should pass and 7 to 8 blocked. Also check 6 to 8 as well. Opposite with switch in right turn mode, pass 7 to 8, block 7 to 6 and 6 to 8. If switch acts different than that it is shorted internally and it will need to be replaced.
If when you jumped C106 you were getting both sides lit at same time then you have short between left and right in body harness.
Got trailer hitch harness? Those are notorious.
If not look up above and to right of e-brake pedal for 14 pin connector C104, this runs everything in the trunk and rear of car. Unplug C104 then plug C106 back in and signal, this will tell you if short is in front or back half of car.
Note flash cadence will be weird while C104 is unplugged, because you are running 1 bulb instead of 2.

Thank you gents. I check the control stalk and it was ok. The only other place where the left and right blink leads (circuits) came close together was in the instrument cluster.

Believe it or not, the oil gauge inside the instrument cluster was causing the short. A while ago the oil gauge leaked and because I could find a replacement, I took it off and soldered the end closed where it was leaking. When putting it back, I didn't put the plastic half moon shaped washer on the inside between the oil gauge and circuit board, but on the outside what you can see here, (http://dieselgiant.com/mbodo13.JPG). Not having that washer caused it to wear through the circuit board coating and short the blinkers.

I simply unscrewed the two small screws for the oil gauge, slid the plastic washer between the oil gauge and circuit board, aligned the holes and put the screws back in.

The crazy part is that this issue didn't show up until 3 years later!

Thank you again for your help.

I have a good oil/temp/fuel cluster for a 123 with English units on the face. I will sell to you for $40 plus shipping (USPS if it fits it ships box appx $10).

It's short a couple bulbs and the rheostat but you should be able to transplant those from yours. The gauges work.

Someone had put the pre-1980 gauge in my 83. The post-1980 is the same physically and electrically just a metric faceplate (bars and deg c) instead of psi and deg f. I wanted stock appearance.

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2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech