Packard Forum Index » V-8 (1955-56)

having issues with the relays on the firewall. the round one is power windows? the other one goes to the ignition switch through both relays down to the starter. wire from ignition is cooked to the relay. any ideas?

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Mike page 40 of this section might help you out,https://www.packardinfo.com/xoops/html/downloads/servicemanual5556/Sect08_Electrical.pdf
Circuit breaker and relay

Almost sounds like someone hooked the battery up in reverse at one time. My 55 is positive ground(+to chassis) If you look at the wire diag on pg 41 of the above posted link "hot" at all time from starter. Seat is hot key off. Ign sw will energize relay and send power to windows only with key so and manual says power seat motors protected thru internal thermal breakers and the windows have the same in the doors so high current should not be pulled thru that wire.

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.

I guess hanging loose like the pic the terminal may have shorted to the body with the ign sw turned on or acc thus overheating that wire but if that is the case all the current would have also flowed thru the sw and done damage there. That wire just energizes the coil windings to pull in the relay contact. The coil is a higher restance and draws fairly low current and due to the design they usually fail open. I have never seen that coil fail shorted. It would have to have some foreign metal inside the relay cover. I think if there was a short and enough current was flowing long enough to burn that wire the ign sw contacts and assoc wiring may well be damage.

The previous owner said he hooked up battery backwards and the wire melted then and the motor no longer turns over I took relays off fire wall to replace them but have not been able to find replacements.

If you post a request here in wanted - for sale someone should be able to help you. You may also try M Borth. Do a net search. He had several he was parting and I did see parts listed as well as v reg and such. Ask others here if they have dealt with hin and if his good used are acceptable.

If you need a ref when rewiring post a request or pm and i can send pix and description so you rewire correctly.