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hartpenn
I'm restoring a 73 and finally vetting thru the electrical system before wiring her up for EV (electrical vehicle) mode. I've upgraded the fuse panel from JWest Engineering, it uses the SmartGlow big blade fuses, very nice. I've replaced the light switch and very carefully wired it back up. I also had to replace the steering column switch as it was cracked but very carefully wired it back up too.

Most wires are terminated correctly but some are not terminated at all but don't believe they contribute to this issue:
1 - Seat belt switch
2 - E-brake switch
3 - Brake switch
4 - Brake warning light switch

When I pull out the flasher switch, the flasher relay buzzes like crazy. It also buzzes when I turn on the turn signals. I initially thought the relay was bad, so I purchased a replacement and it does the same thing. I've even disconnected the flasher relay switch and hard-wired using jumpers and acheive the same results. One interesting note: when I jump 30 (non-switched power) to 49 (relay power A) and try to jump 33 (Gnd) to 49a (relay power B), it buzzes. 49 and 49a should just energize the relay, correct?

I thnk this smacks of a short somewhere, steering column switch maybe, cause its very tight in there for so many wires. I know I've made a lot of changes and thus very difficult to pin down but just thought I'd toss it out to the crowd. I've been stumped for days. Any suggestions would be highly appreciated.

Thanks,
Hart
hartpenn
QUOTE(hartpenn @ Sep 19 2010, 02:41 PM) *

I'm restoring a 73 and finally vetting thru the electrical system before wiring her up for EV (electrical vehicle) mode. I've upgraded the fuse panel from JWest Engineering, it uses the SmartGlow big blade fuses, very nice. I've replaced the light switch and very carefully wired it back up. I also had to replace the steering column switch as it was cracked but very carefully wired it back up too.

Most wires are terminated correctly but some are not terminated at all but don't believe they contribute to this issue:
1 - Seat belt switch
2 - E-brake switch
3 - Brake switch
4 - Brake warning light switch

When I pull out the flasher switch, the flasher relay buzzes like crazy. It also buzzes when I turn on the turn signals. I initially thought the relay was bad, so I purchased a replacement and it does the same thing. I've even disconnected the flasher relay switch and hard-wired using jumpers and acheive the same results. One interesting note: when I jump 30 (non-switched power) to 49 (relay power A) and try to jump 33 (Gnd) to 49a (relay power sunglasses.gif, it buzzes. 49 and 49a should just energize the relay, correct?

I thnk this smacks of a short somewhere, steering column switch maybe, cause its very tight in there for so many wires. I know I've made a lot of changes and thus very difficult to pin down but just thought I'd toss it out to the crowd. I've been stumped for days. Any suggestions would be highly appreciated.

Thanks,
Hart



I'm extremely embarassed to admit this but for the community's sake it must be done. icon8.gif As my battery had died, I was using a Schumacher battery charger to supply the car's voltage and it did so well enough to do most testing and troubleshooting for the headlights and motors. Using an oscilloscope, I was able to determine that the dc signal was just dirty enough (clipped sine waves) to cause the oscillation in the relay. headbang.gif I actually hooked up the relay seperately to the charger via (+) 49 and (-) 31 and then connected the rear trunk light to 49a and 31 too. It buzzed like a mother. Problem solved. I'll go out and get another battery tomorrow. Who'd a thunk it?
Tom
Hart,
Nothing to be embarassed about. And good find! I doubt most would think to check the output of the charger.
Battery chargers are usually not very well filtered and have varying amounts of AC ripple on the DC level. I don't think batteries care much, but other components see this differently.
Tom
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