Fast blinking right turn signal, but bulbs good?
 

Hi all.

When I first got my 1988 300SEL, the left front turn signal bulb was blown, which was setting off the blown bulb warning lamp on the instrument panel and I was getting the fast blinking on the right side.

I replaced the bulb and all seems fine, but I still get an occasional warning of a blown bulb and the fast blinking, BUT this time, BOTH front and rear signal are working. Whats strange is it will blink normal for about 5 times, then flash fast for about 10, then slow for a few times, then fast, etc? The bulbs are tight and the connections seem fine, because the lights are working. The left side works perfectly.

Does anyone have any clue as to whats going on? Faulty sensor or flasher?

Thanks!

might want to check your flasher switch out. Check for corrison and bad grounds as well at the signals.

Wow, that was a fast reply!

Where is the flasher switch located? Thanks.

Did you buy the correct bulbs for the car? If they have a brass base they are most likely NOT the correct bulbs. The correct ones will typicaly have a silver base. The brass based US spec bulbs can have differnt current ratings than the European spec bulbs despite sharing the same socket footprint. The brass based bulbs can cause problems with the blinker, bulb warning, and cruise control. Making sure you have the right bulbs is the first step. A good test is to swap bulbs with the right side and see in the problem follows or stays with the left side.

Thanks. Well, I was in Wal-Mart when I bought them. I bought the ones that the computer stated it needed. Maybe I need a different brand? I think the base was silver, not brass.

I will check it out though.

check to see if the headlight and fog light harnesses are correct plugged in. in my haste one day, i switched them. I had fast blinking madness for a few days until I dug in there and had a "Doh" moment. ricers would want to race me...j/k.

I was thinking wattage....if its not right it will blink too fast or too slow....my dad's SD had non-german bulbs in it when we bought it and it had too slow of a blink. German bulbs fixed the problem. :D

I've most often had erratic rapid flashing when I had a bulb socket loose or corroded.

My quick fix was to remove the bulb, then use a set of needle nose pliers to pull the center contact up enough to put more tension in it so that it held the bulb securely when installed again.

Also, In addition, if you get stumped....check the lamps/holders for corrosion build up .. a real problem in those and they add more Resistance to the circuit..causing the flasher to weird out on you..

swap the bulbs with the other side to isolate the fault.
This is how i sorted mine .
mak
300se

bring up a wiring diagram of the exterior lighting or turn signals and on there it will tell you, dont know off the top my head.

Answer
 

Main fuse box under hood, in false bulkhead area.

MB# 2018210247

http://catalog.peachparts.com/item.wws?sku=W0133-1618689








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