Gremlins in my '77 620

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METSystem
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Gremlins in my '77 620

#1

Post by METSystem » Sat Aug 16, 2014 2:42 pm

Oh I got a lovely problem out of nowhere. The truck doesn't get driven much, but I do go out and start it once every time I fire up the barbecue, which is about every 2 to 4 weeks. This time, however, the truck was completely dead. No power, the battery had been completely drained. So the next day I put my handy dandy battery charger on it, and put it on a trickle charge. Almost 2 hours later, my son Geno, comes in and says, "Dad, why is the right taillight on on the Datsun?" I suggested that he may have found our battery drainer. . . Which I'm certain that he had, went outside, sure enough that light was on! So, I went to check the turn signal lever in the cab. . . It was in the off position. No key in the ignition either, of course. Turned the right signal on, "Dad, the light went off!" Huh? Turned it to the left turn signal, light came back on and no left light. I looked up front, no front light is on at all. So I turned on the headlights. . . . . Oh boy. . . No headlights! No high beams either! Nothing but that right rear turn signal shining bright when the truck is supposed to be at rest! The truck started fine, I went through everything again with the truck running still no change in everything I explained above. . . AND no brake lights!

My step-Dad is an old car guy, and his first question to me was, "It's not Lucas Electric's is it?"
LOL. "No Mike, it's Japanese, they only drive on the left side of the road like the Brits."

So. . . Has anyone ever even heard of such a gremlin in their days? And where is the place to start with this in search of a cure?!
There comes a time when reliving your youth, requires the acquisition of a Datsun, like the one you drove in high school and the other one when you were just done with college. The issue then becomes. . . Fitting again, behind the wheel!

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Laecaon
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Re: Gremlins in my '77 620

#2

Post by Laecaon » Sat Aug 16, 2014 3:37 pm

That is an odd one.

Lets think of a few things. Headlights should be battery power, brake lights are battery power. Turn signals are ignition power. On a 620 the Turn signal and the Brake lights are the same filaments inside the bulbs.

Now considering that your turn signal stock controls all lights except running lights (yes it is also the high beam switch, which then chooses which circuit has power). Something is likely off with that. But I would say that doesnt explain the lack of headlights.

Go unplug the brake switch. That should turn the light off in the back... as that should be where the power is coming from (and your turn signal stock is inappropriately routing power back there).

Ill try to think about this some more, but the lack of headlights and running lights bothers me.

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METSystem
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Re: Gremlins in my '77 620

#3

Post by METSystem » Sun Aug 17, 2014 6:29 pm

Driving without headlights during the day, no problem. Driving short distances without using turn signals, the hand signals can work in a short pinch. But no brake lights. . . I won't even leave the driveway!
There comes a time when reliving your youth, requires the acquisition of a Datsun, like the one you drove in high school and the other one when you were just done with college. The issue then becomes. . . Fitting again, behind the wheel!

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METSystem
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Re: Gremlins in my '77 620

#4

Post by METSystem » Thu Aug 21, 2014 5:17 pm

Hey! I think we may have found the problem! The kids and I went out to harvest the garden, and I had them start the Datsun. . . It had to get charged again, so we let it run while we picked tomatoes, green beans, squash and Swiss Chard. After all was said and done, about 30 minutes after the Datsun was idling all by his lonesome, I had my son shut him down, and we lowered the hood and put stuff away. . . . Ready? Here's the good part. . . .

I never disconnected the brake switch as was prescribed. The engine was off, the truck was locked up, and both taillights were on! I went around front, no headlights, but I did have taillights! I got back into the truck, turned on the headlights, still no headlights (another issue all together now), but . . . The taillights are still on! I had my son trade places with me, and had him step on the brake. . . NO brake lights, but the taillights were still on! That to me indicates that the brake lights are stuck on, so chances are (in my estimation), that the brake light switch has gone :boobs: up!

The headlights, I'm still not sure what is going on there though. . . Let me know if you think my conclusion is faulty please. . . Thanks Guys!
There comes a time when reliving your youth, requires the acquisition of a Datsun, like the one you drove in high school and the other one when you were just done with college. The issue then becomes. . . Fitting again, behind the wheel!

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Laecaon
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Re: Gremlins in my '77 620

#5

Post by Laecaon » Thu Aug 21, 2014 5:43 pm

Some datsuns have a rubber piece on the brake switch, it often fails, and the swith doesn't get presses all the way on. Get under the dash and push the switch with your finger, the lights should turn off.

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METSystem
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Re: Gremlins in my '77 620

#6

Post by METSystem » Thu Aug 21, 2014 7:10 pm

Laecaon » Thu Aug 21, 2014 6:43 pm wrote:Some datsuns have a rubber piece on the brake switch, it often fails, and the swith doesn't get presses all the way on. Get under the dash and push the switch with your finger, the lights should turn off.
What is it? A stopper/pad kinda thingamagiggy? (Yeah, I used to be a parts guy. . . Got lotsa that! LOL)
There comes a time when reliving your youth, requires the acquisition of a Datsun, like the one you drove in high school and the other one when you were just done with college. The issue then becomes. . . Fitting again, behind the wheel!

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