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Drove my packard at night for the first time yesterday and realized my headlights were turning off and then back on even during acceleration. Ammeter shows charging under acceleration and drops below centerline at idle. I'm assuming it all comes back to the regulator issue but is their anything else I should pick up from the parts store to fix this?

You may have a short circuit in the lighting circuit and what you're observing is the headlight circuit breaker opening and then resetting.

The description of your ammeter function sounds entirely normal with respect to the charging circuit itself - that is what generators do, they charge at engine speeds above a fast idle, but don't charge at idle, so what makes you think you have a regulator problem?

Some possibilities come to mind. The circuit breaker on the headlight switch is self resetting. If something has shorted it will cut off, wait a bit and come back on then go off again. The cycle continues until the breaker fails or maybe something vibrates and the short goes away.

Another possibility is age has weakened the breaker or possibly dirty connections are pulling excess current. Believe breaker is rated at 30 amps but if high beam and all the other lights attached to the headlight switch and circuits with possibly some dirty or high resistance connections have it running near it's limit, the trip mechanism may heat up and cycle early.

Some have had issues with the dimmer switch so always a possibility worth looking at with both shorts and high resistance. Some not too obvious places to look for shorts is where the cable to headlight buckets pass thru fender and in the trunk. Check the tail lamp sockets for something pressing or falling against the wire where it enters socket and also where the loom crosses over to right side under the latch area. Something could have damaged that stretch or the grommet where license light wire exits the trunk floor could be gone and wire is unprotected.

I am really starting to see a lot of these circuit breakers no longer having their rated capacity and the lights consequently cycling. Also, the dimmer switches are getting dodgy on even really well kept cars. They are only operating a factor of six times outside of their designed life span!

Anyway, Napa has both items for not much money and that well spent. The circuit breaker is on the back of your headlight switch.

Awesome, I did find a disconnected wire In the trunk, I believe it is my license plate light. It also seems the wires seem to be crossed. Can anyone post pics of a wiring diagram I cannot access this with the iPhone. I was always under the impression if your headlights brighten upon acceleration the regulator would be the culprit...

Here's 3 pages showing the light wiring -- starting from front of car. Hope you can zoom enough to see the wire color detail so you can trace page to page.

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I have gone through lots of wiring issues on my 23rd series Deluxe 8 including a new harness. The trunk area has a number of wires in the rear with almost no mechanical protection. If you have "junk in the trunk" as I do these wires can get bent crushed, dinged, shorted, and even disconnected. Old crumbling insulation and missing or cracked rubber gromments make these problems worse. If I was redesigning a Packard I would have put a simple cover ahead of the wires so they are protected.

I have found that there is no good fix for old wiring other than replacing it or at least putting on new insulation (like a tape wrap or shrink tubing). Also cleaning up the wire connections helps a lot with dim lights and intermittant connections.