turn signals

[Ed Fisher]

Hey gang:  The driver's side front turn signal lamp doesn't work on my 1964 230sl with euro headlamps.  When I remove the bulb and check the voltage on the terminals I can see the fluctuation of the meter that coincides with the flasher making/breaking.  When I put in an 1156 bulb, or the old bulb which tests good ohmically, the voltage fluctuation drops to zero as if the loading of the bulb is dropping the voltage.  Also, I can see the voltage, without the bulb, on the casing of the socket and the tab.  I have cleaned socket, tab, and grounding lug in the headlight bucket to no avail.  Any ideas?

Thanks,

Ed Fisher
Dallas

[Malc]

Ed,
You may get the volts but your not getting the power (watts). I suggest that you carefully check that the earth(ground) is good (less than 2 - 3 Ohms) Then start working your way back through all the connectors to check for corrosion/dirt. Clean with a brass wire brush or a 3M style Scotbright pad.
One trick is to break each connection (using a bulb similar to the one you want to use in your turn signal 12v / 21watt with two flying leads)connect one wire to the feed and one to a good earth point and see if illuminates. Yes? then the fault is "downstream" if not it's "upstream" if you know what I mean.
Another point is that wire can corrode / break / fray under the plastic sheath, so if you find power at a connector jump from this point to your turn signal with another wire, If the signal then works ok the wire is suspect
Hope this helps
Malc
Scotland

[knirk]

Malc,
when you check the ground with an Ohm-meter, do you put one terminal on the ground wire and the other on the battery minus pole?

Per G. Birkeland
69 280 sl aut 834
Norway

[Malc]

quote:Originally posted by knirk

Malc,
when you check the ground with an Ohm-meter, do you put one terminal on the ground wire and the other on the battery minus pole?

Per G. Birkeland
69 280 sl aut 834
Norway

Per,
That will work. In Ed's case I would set the meter on Ohmms, then one lead on the earth (ground)for the indicator (turn signal) bulb and the other on the battery to see what I get. THat can tell you several things though, bad earth from battery to chassis or the bulb lead, so I would probably make sure the earth from the light was good to the chassis/body first, then make sure the earth from the battery to the chassis was also good.
Having messed about with cars and bikes for too long most electrical problems I have found are due to bad earthing, corroded connections and wires, butchered wiring harnesses and the dreaded "scotch lock" connectors
Cheers
MAlc
PS where in Norway are you? I sometimes visit Stavanger and Bergen

[knirk]

Malc,

I live just outside Kristiansand on the southern costline of Norway. I visit Stavanger and Bergen from time to time at work. Give me a mail next time you are there.

Per G. Birkeland
69 280 sl aut 834
Norway

[Ed Fisher]

Well friends, after cleaning things up a bit and having the turn signals not work, posting my question to the group, and awaiting time to troubleshoot further the drivers side signal has decided to work!  But, alas, the passenger side quit, so I began disassembling the front headlamp assembly and promptly broke off two of the retaining screws.  I am now awaiting an M4 tap and a 3.3mm drill.  I did get the turnsignals to work though....

Thanks for all the help, and hope that my patience continues.

Ed Fisher