Packard Forum Index » V-8 (1955-56)

The instrument panel dimmer switch is not working on my '56 Clipper. It was working just fine, up to about a year ago. It is not illuminating the instrument panel. The switch operates the headlights, tail lights and parking lights. The map light also works when I twist the switch fully counter clockwise.

Attached is a picture of the switch, from behind the dash. I can't tell if a wire is missing to one of the connectors.

Any suggestions on troubleshooting is much appreciated. Also, does anyone have a diagram showing the wiring to the switch?

I'd like to get this instrument panel lights working before heading into the fall and winter seasons here in the Pacific Northwest.

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The headlight switch is notorious for the contacts oxidizing on the rheostat section and killing instrument lights.

Factory wiring is the lights are powered via a short jumper from the double tail light terminal in the middle of the switch to a single outer terminal on the ceramic section same side as the tail light terminal. They are on with the headlight switch in either position and are dimmed or turned off by the combo rheostat/switch. Dash lights come off a double terminal in the center of the ceramic. The single terminal on the opposite side of the switch is for the courtesy lights and gets grounded when the switch is turned to the left.

The rheostat section of the switch is not able to be removed for cleaning easily because rivets have to be drilled out and then replaced with something. You may have some luck with contact cleaner but generally you can't direct the spray unless the switch is out of the car. You can bend the tabs and disassemble the switch section and then remove the shaft and wipers for a partial cleaning. If the rivets holding the terminals have loosened and oxidation has started between the terminals and rheostat sections it is usually a futile effort to keep it from recurring.

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Thank you for the images. It looks like I'm missing the jumper wire. I ordered the special tool to remove the switch. Hopefully I can just replace that jumper wire, and not spend the money on replacing the switch.

A male .156 diameter bullet terminal which you can pick up at most parts stores will work for the switch terminals.

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I was just about to ask about the connector; thanks. Also, what type (gauge) of wire do I use?

You only need about 6" so 18ga is fine if you already have a short piece. I like 16ga if you need to buy a length. 16ga is used all over the car so would be useful for more than one job.

An option for dash lights that will function but not dim is to power them off the tail light circuit. It is on with both the parking light position and the headlight position.

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Having owned a lot of old cars and a small fleet of V8 Packards over the years, the one thing that seems to be common with most of them is the rheostat for instrument panel lights stop working after long periods of not being used to dim the dash lights.

The most common malady I've discovered is that the coils and /or the contact for same become oxidized. This is especially common when the switch/fader feature is not used for long periods. One very, very easy remedy I discovered back in the 1970s was simply to cycle the rheostat back and forth about 25-30 times. The friction over the coiling usually cuts through any built-up oxidation and everything gradually begins to work again.

An even better remedy I have used over the years was a spray can of tuner cleaner or carbon tet... (used to get these from Radio Shack stores). Spray over the rheostat coiling and contact segment, cycle back and forth... and voila! Also worked wonders of Packard V8 Factory Air Conditioning main rheostat control. Same process.

After getting that special tool to remove the switch from the dash, it appears that the hidden hex nut is stripped. Any suggestions on how to remove the hidden hex nut when it is stripped?

The tool works to remove the bezel of electric antenna switch; so, I now know how the bezel's hex nut threads onto the switch.

It is the hex nut on the bezel of the headlight switch that is stripped; rendering the tool useless.

Ugh!