Electrical issue (strange!)

[Cougar]

In regards to the head lamp circuit I forgot that the plug was removed to the head light when the voltage measurement was taken so the voltage that was seen on the white wire while the high beams were off was coming from another area. Possibly the high beam indicator light in the dash. The same results takes place. You just need to know how things are wired together in order to understand what is happening when you make a voltage measurement. You can be misled if you aren't careful.

 

As far as the relay coil and the head lamp being tied to the white wire go, it is not a problem having the two paralleled together. The small extra current needed to run the relay coil will just add to the current needed to run the head light, insignificant compared to the light current needed. So no prob-lemo.

Edited September 1, 2009 by Cougar

[89Ru]

The potential problem I see is that when the high beams are selected, current will be flowing from the green wire, through the filament, and then to ground through the white wire. Will this current flowing through the white wire when the high beams are on interfere with the trigger circuit's path to ground through the same white wire?

 

No problem at all, like Cougar said, the high beam filament and the relay coil are in parallel. Those electrons won't get mixed up between the parallel circuits, they'll find there way back to the battery (-) sharing that white wire. Just make sure you wire in the switch somewhere in series with the relay coil loop or the driving lights will be on all the time (when your high beams are on).

[BrightLights]

No problem at all, like Cougar said, the high beam filament and the relay coil are in parallel. Those electrons won't get mixed up between the parallel circuits, they'll find there way back to the battery (-) sharing that white wire. Just make sure you wire in the switch somewhere in series with the relay coil loop or the driving lights will be on all the time (when your high beams are on).

 

Thanks to both Cougar and 89Ru and everybody else who has helped me. Yes, the wire from pin #85 of the relay will first go to my driver's position toggle switch and then to a splice into the white wire. It means running another small guage wire through the grommet in the firewall, but *that* I know how to do.

 

Thanks again - this sounds completely right to me.

[Cougar]

You're welcome for the help.

[89Ru]

Of course, my job is to fabricate wild ideas to balance the common sense of the rest.

 

By the way welcome to the board

[OB99W]

I like your thought about the key OB99W. There may be RFI coming from the starter motor and the lead is causing the noise to get to places it shouldn't and is causing trouble.

I'm not sure we'll ever know exactly what the original weirdness was, but http://endwrench.com/images/pdfs/07FebInter.EW.II.pdf could be a clue for some strange immobilizer behaviour.