1003 Headlight and horn wiring

Discussions related to electrical and fuel system, gasoline, etc.

1003 Headlight and horn wiring

Postby DWS1003 » Thu Sep 24, 2009 7:31 pm

I need the proper connections for the headlight wires on my '33 1003 Su 8. The plugs in the base of the headlights are labeled 1-2-3-4-G The right light has connectors in 1-2-3 and G, and no connector in 4. Thus, I assume 4 is for parking lamp if not equipped with fender lamps and G is ground. The left light has connectors for 1-2-G

I also need to find a source of the small "bullet" terminals for the wire to plug into the base of the headlights.

I am confused on the horn wiring - as both a hot wire (from the generator cable in the harness) and a ground wire (from the switch) are shown to be routed. One wire remnant is going into the horn cover to a terminal. I am unsure where the ground wire connects. This would imply that the horns are insulated from the body ground, but I do not see how.

THANKS for the help
Attachments
P1120609.JPG
P1120612.JPG
Darrell
Indianapolis, IN
1933 Packard 1003 Super 8
92 Porsche C4, 93 Porsche C4, assorted Honda's, Toyotas, ....
DWS1003
 
Posts: 11
Joined: Tue Sep 01, 2009 9:02 am

Re: 1003 Headlight and horn wiring

Postby Dave Czirr » Fri Sep 25, 2009 5:31 am

Your headlights should be the same as my 1934 Eight, using the triple-filament Madza 3003 bulb with 3 bayonet pins on the shell and 3 lead button contacts. I've never had my headlights apart so I'm hoping someone else will come along to help, but perhaps this diagram of the headlight switch wiring, from the 1933-34 Service Letters, will help you unravel the problem.

Sorry, can't help much on the horns as 33 and 34 had different units; my 34 horns have a single hot lead, no ground wire, and although they have rubber insulator blocks between the mounting ears, it has a metal-to-metal ground to the headlight support casting. Have you checked the horn relay (driver's side, near front of engine by splasher, should have "RBM" embossed into the metal cover)? One wire should be power, one should go to the horns, and the other should go up the center of the steering column and ultimately to ground when the horn button is pushed - entirely a conventional horn wiring setup.
Attachments
34 Light Switch.JPG
Dave Czirr
Moderator
 
Posts: 2934
Joined: Tue Jun 16, 2009 5:30 am
Location: New Jersey

Re: 1003 Headlight and horn wiring

Postby DWS1003 » Fri Sep 25, 2009 5:54 am

Thanks Dave - helpful as always

Yes, the headlights are the same.The switch wiring diagram helps confirm what I already have in my harness, but it is still not clear which plug in the headlight base is "pass", "tilt", etc. It is interesting that only two of the filaments are used in the left light vs all three in the right. The plugs in the base are there to allow you to disconnect the headlights when removing them from the headlight support casting. If you are feeling especially adventuresome, you might loosen and remove the pinch bolt on the casting and slide out one of the headlights and note the relationship of the wire color to the port. Don't drop that light.

The horns appear to have an insulator block on the mounting, but there is continuity between the support casting and the horn, so this still doesn't make sense. '33's did not use a horn relay, as I can tell from the wiring diagrams and the parts book. The engineers obviously quickly recognized that a relay should really be used for the horns. I may actually add this hidden improvement to my wiring.
Darrell
Indianapolis, IN
1933 Packard 1003 Super 8
92 Porsche C4, 93 Porsche C4, assorted Honda's, Toyotas, ....
DWS1003
 
Posts: 11
Joined: Tue Sep 01, 2009 9:02 am

Re: 1003 Headlight and horn wiring

Postby Dave Czirr » Fri Sep 25, 2009 6:44 am

Darrell, glad I could be of some assistance. I'm usually against modifications and hadn't realized the 33s didn't use a horn relay. Given the amount of current they draw and the nature and age of the contacts on the horn button, discretely adding a horn relay sounds like a really good idea to me. No doubt you know that Echlin (NAPA) and others offer a range of universal horn relays.

I'm guessing by looking at the headlight aiming information that the reason the 3rd filament was only used in the right-side headlight was to better illuminate the side of the road without blinding (can anyone call the output of these headlamps blinding? even with resilvered reflectors?) oncoming traffic. I only wish DOT would be sensitive to that with today's headlamps - especially those blue burners!!
Dave Czirr
Moderator
 
Posts: 2934
Joined: Tue Jun 16, 2009 5:30 am
Location: New Jersey


Return to Electrical & Fuel

Who is online

Users browsing this forum: No registered users and 1 guest