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I took my Packard out to a car show on Father's Day this past weekend and a fellow who was following me told me I had no brakes lights. Then I discovered later on my passenger side front turn signal wasn't working either. So, I have headlights, taillights, rear turn signals but only the driver' side front turn signal. I went through and checked the wiring but can't figure out where the problem lies, but it must be shorting out somewhere. I'm no electrician and don't know where to begin; it's very frustrating.

Now I will say I recently re-installed my glovebox clock, but found it didn't work, so I unhooked the power wire, but left the wires for the clock light hooked up.

And then I installed a new horn relay, as the old one wasn't working properly. I now have a nicer sounding horn, and a non-functioning clock that visually plugs the glovebox hole in my dashboard. Did I do something wrong? Should I unhook the clock completely and test the brake lights again? Any help from you guys, (the experts) would be greatly appreciated.

Thanks,
Steve Weaver

Why do you think there's a short? A short would either trip the circuit breaker, or melt your wiring harness.

Did you check whether your bulbs are burnt out? If so, then your charging system voltage is set way too high.

Did you check the fuses?? The rear lights fuse will kill the brake lights.

If the bulbs and fuses are ok, then it's likely a wiring harness problem (broken wire at a terminal, for example).

packardinfo.com/xoops/html/modules/archi ... p?catID=50&cat_pid=56&ContentID=260

Hi fellow Pittsburgher,

I checked the front, passenger side turn signal bulb, and it's okay, just doesn't work. Are there separate bulbs for the rear brake lights, as both rear turn signals are working, as well as the rear lights when turned on. Just no brake lights. I was just guessing on a short circuit or maybe something else. Where do you find a circuit breaker for this year Packard? There is only a single fuse located on top of the pull-out light knob/switch under the dash.

I guess I'll go back and unhook the clock harness of the two remaining wires for the ground and light for the clock operation.

Attached is an illustration of the headlight switch under the dash showing the terminals and different colored wires.

Attach file:

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  Diagram of headlight switch.jpg (61.10 KB)

The brake light switch is located on the brake master cylinder. It has 2 wires connected to it. Connecting those 2 wires together will cause the brake lights to work IF the switch is bad but the rest of the system is OK. Do not allow any bare wires or connections to touch any metal part of the car. Be very careful with old wiring and electrical connections. I suspect that the front turn signal failure is a bad bulb or dirt/corrosion in the bulb socket.

I agree, if it's literally just those three things, then it's just a coincidence.

Did you see the schematic I posted? You have a circuit breaker on the junction block as well as some fuses. The Stop Light fuse would keep the brake lights from working; check it.

I'm confused by your mention of turn signals. Did they have them as factory equipment in 1937? If so, I don't see them on the diagram.

It says you're in Muncie? Are you in Pittsburgh now?

Hi again,

Sorry I'm late getting back with all you guys; I got called away. No, I live in Muncie but still have family back in Mars, PA.

Yes, I saw your schematics and they are a lot better looking than page 9 of my shop manual, Fig. 11A showing almost the same thing, but yours is much clearer. Thank you.

So, I checked all the bulbs in the taillights and they're okay. The turn signals are add-ons in the front (picture attached).
I also unhooked the clock wiring harness in case that was part/or all of the problem. Nothing new after unhooking the harness.

I can't find any stoplight switch (9A) on the steering post cable (9B) of the schematics. There's a wire bundle to/from the aftermarket turn signal handle on the steering column. (pictures attached).

I was talking to a fellow car shower on Sunday, and he said he had a similar problem with his brake lights. He said there is a wire that came loose near the brake master cylinder. So, I checked all around in the engine bay of my car and don't recognize anything like a master cylinder. Is it hidden somewhere I'm not looking?

Steve

The brake light switch is hydraulic and can be found on the master brake cylinder. When the brake lights went out on my 1940 110, it turned out to be an intermittent short on the trunk light wire that was causing the fuse to blow so check fuses too. As TxGoat already said, disconnect the two wires from the switch, measure each to see if there is power. If there is, then jumper the two together and see if the lights are on. If they are, then it's the switch. If neither has power, then it's a fuse or something in the wiring but the clock has nothing whatsoever to do with it.

The master cylinder is on the inside of the drivers side frame rail just forward of the firewall. If you have the stock hydraulic brake light switch, it should have two wires attached to the front end of the master cylinder via the brakelight switch. You can source a replacement at Napa, and do not need to bleed the brakes if you change the switch quickly.

The brake switch is a known failure item and should be checked first. If that seems to be OK also check to see if the aftermarket turn signal switch has the brake light signal wired to go thru it. If it does, there could be a problem in that area.

SOME but not all of the aftermarket signal kits tried to add a more modern approach to the signals by taking the wire coming from the brake switch that would normally go straight to the brake lights in a completely stock 37 and run it thru the added turn signal switch first. Doing that along with a second mod of adding another wire to the rear to run alongside the loom containing the original wire to the brake light bulbs make it so you can add the turn signal function into the two existing rear stop light bulbs instead of having to add additional bulbs in the rear.

Packard factory turn signals had the added rear bulbs from the advent of their offering the option until the 23rd series when they too routed the brake light signal thru the turn switch as other mfgs were doing and used the brake lights for turn signals too.

Pretty sure if you follow your brake pedal it will lead you to the master cylinder

It's also shown on the part diagram:packardinfo.com/xoops/html/modules/parts ... lateNumber=2401&partslist=1935-1941

It's almost certainly either the Stop Light fuse or the brake switch, so check both.