And now the tail lights.....

[Drakeule]

Yes, I am the guy with the gas tank sender problem. It magically healed itself, it seems, at the expense of a short in the tail lights!

 

I originally had this short appear last week; according to the manual, if you get flashing lights on both the parking switch and the headlight position, you have a short in the tail lights.

 

I thought that I had solved it by fiddling with the LR tail light. No more short. However, after taking apart the 6 way connector under the dash to clean it, my shorting problem started again.

 

I disconnected both rear lights and still get the blinking up front. Of course, when I disconnect the 6 way connector, the front parking and headlights are fine. I plan on teasing out the short with an ohmmeter, connecting each of the 2 bulb connections and the corresponding pin in the 6 way; it should be only 2 of these pins that supply juice to the parking/stop lights. The other pins appear to supply juice to the turn signals (which work just fine), the dome light,  and that pesky gas tank sender.

 

I just pray that the short isn't between the top of the trunk and the 6 way; virtually impossible to replace that wire through the roof. I guess I would have to re route a new wire from the switch back to the trunk, most probably just along the inside (or outside) of the floor.

 

I would appreciate any sagacious input whatsoever, especially about teasing out just exactly where that short lies.

 

CD, Potomac, Md.

[DonMicheletti]

You could disconnect the plug under the dash, disconnect all the tail lights and gas tank connectors in the trunk.

With an ohmeter see which wire, via the trunk connectors shows a short to the ground.

Not much you can do about that, unless the short is in the trunk area.

[Ben Bruce aka First Born]

Poor grounds are HELL.

 

Ben

[EmTee]

Yes, but a poor ground won't burn-up the harness (and possibly the car).  It sounds like there is an intermittent short that needs to be identified.  Follow Don's recommendation to identify where the problem is.  If it turns out that it is in the section of the harness that runs through the roof you may choose to run a separate wire following a path that is accessible.  At some point later the original harness section can be replaced when the interior is out.

[Drakeule]

Unfortunately, I think you guys are right; I am about to test the 6 way back to the tail lights for the short,as well as the other female side of the plug back to the 6V source (switch.)

 

Also, the stop light circuit. BTW, does anybody know where the stop light switch lives?

[neil morse]

2 hours ago, Drakeule said:

Also, the stop light circuit. BTW, does anybody know where the stop light switch lives?

On my '41, it's right in front of the master cylinder on the left side of the engine, toward the rear.

[Drakeule]

OK, more weird readings...I checked the 6 way connector with a continuity (ohm) meter. I got a total of 5 short conditions out of 6 pins! This can't be right, as the gas gauge (now) and the turn signal lights work fine!

 

I then checked again back at the rear lights; It looks like the parking light circuit might be the culprit. I guess I'll make a test harness and cut the wire back at the parking lights and attach it directly to the number 2 arm on the light switch. This should help in further diagnosis.

 

I may just, in the end, replicate the 5 wire loom, get another male pin connector, and snake it back to the trunk. Does Old Buick parts sell that section? I don't see it listed.

 

Maybe just get that 6 pin connector. Anybody have a source on this?

[EmTee]

Remove all of the bulbs so that you're not fooled by a burned-out bulb with a shorted filament.

[Drakeule]

Well, after teasing out the stop light circuit (and finding out that the switch is faulty), magically, the short has "disappeared". I have been fiddling with the rear harness, and may have pulled the offending tail light wire away from the body.

 

While I don't believe in cars "healing themselves", maybe I am on to something. Also, EmTee suggested checking all those bulbs and I did so with the trunk light: I saw some sparking upon removing the bulb to check it. Bulb was fine; perhaps that short is in the trunk light wire?

 

Only time will tell.....thanks to all for offering that sagacious advice! If the short comes back, I will continue to whine on this thread!

 

CD

[Gary W]

Or the trunk light socket..  I rebuilt all my sockets because the small insulator disc breaks down and can allow the wires to touch either the socket wall or each other.

[Drakeule]

Gary W:

 

Ahhhh....I think that you may be on to something here. I will keep vigilant watch on that trunk light!

 

And, love that newly wed haulin' 37 !

[RiKi5156B]

On my 40 sedan the factory rear light sockets were ok but the terminal part was destroyed. I went to u pullit and clear in the back row of gm cars was a 67 pontiac catalina. looked in the trunk and the snap in taillight sockets were there. Cut the wires long and snapped them out. Got home and they snapped right in to the 40s housings.

[RiKi5156B]