740 GLE wagon 1986 Signal lights/Hazard flasher erratic

renarddumarais · Post by **renarddumarais** » 21 Dec 2009, 20:15

Since cooler weather has arrived (still trying to blame the weather for my electrical problem), my turn signals and emergency flasher work on an undependable basis. When I switch on turn signals, the lights might flash until turn is completed, flash two or three times and stop, or not flash at all. The hazard flasher will not work when the signals don't work... that makes sense. I have changed out the old switch assembly on the steering column, but that didn't alleviate the problem. I'm thinking fortuitous wiring connection, relay or a flasher timer somewhere. Have any of you gurus encountered this one??

Post by **billofdurham** » 22 Dec 2009, 11:18

The cold weather could be to blame. Having changed the switch I would be looking at the turn signal relay. It is the centre relay on the middle row on the relay board. The next time you have this problem give it a good hard flick with your finger. That may kick it back into life.

The relay could be the original and now have a bad solder joint which may become worse in cold weather. If you are handy you can open a relay and re-solder any bad joints.

Bill.

renarddumarais · Post by **renarddumarais** » 30 Dec 2009, 04:14

Mornin', Billofdurham: I tapped the flasher relay and it does, indeed, start up the signals/flashers...sometimes for only a few cycles and then it's kaput again. I opened up the device and examined it with a jeweler's loupe but could find no cracks in the circuit tracks. There's a computer chip with eight pins in there (probably a timer chip) along with a coil, and a capacitor. Any of those could be the failing component aggravated by cold temps. The relay has been around for almost 299,000 miles so it has done its duty. I have a new one coming via for $8 US. The original was made in Germany, the new one in Tunisia. It's a thousand wonders the electrical system works at all as I had a melt-down a few years ago when the hot battery cable shorted out to the engine block. The immediate noticeable damage was a vaporized woven ground cable between the block and firewall, and the emergency brake and kick-down cables were fused to their sheaths. It's no doubt a good thing the ignition switch was turned off at the time of this event. Thanks for the insight.

Post by **billofdurham** » 30 Dec 2009, 13:00

You are welcome. Thank you for the update.

Bill.

renarddumarais · Post by **renarddumarais** » 03 Feb 2010, 21:36

Back at last. The new relay did the trick. The temperature has been down to 8 degrees F and the flasher/signals worked fine. Thanks, Bill!

Post by **billofdurham** » 04 Feb 2010, 07:31

Thank you for the update.

Bill.