Re: relays on firewall

Posted by HH56 On 2015/4/4 13:25:02

Don't think polarity is the issue with the burned wire. I think the relay was damaged so there was a short internally or maybe the wire terminal was bent or damaged and shorted to ground. The wire from ign switch just turns on the relay to make the windows and seat operative.

Nothing on a stock Packard is polarity sensitive as evidenced by the same motors and relays wired the same way being used on the windows and seat. Same with the starter and heater fan or blower motors. Several have accidentally or purposely changed their cars to negative ground. Other than needing to reverse the ammeter and repolarize the generator so it can charge in the opposite configuration the car never knew the difference. Even the regulator which is supposed to be in a pos or neg configuration seems to still function -- how well or long might be a question though.

Not sure if the rebuilt solid state compensator boxes are sensitive but if someone installed a solid state radio vibrator those are polarity sensitive and would be the only things that could give problems. If any of the motors have been changed or something aftermarket installed so that a permanent magnet motor or control circuit is used then those are definitely sensitive.