Idiot lights won't go off

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mentalQtip
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Idiot lights won't go off

Post by mentalQtip » Fri Jun 12, 2015 5:48 pm

'74 thing with solex 34 pict 3 and generator.

The oil light wasn't working and while trying to track down the problem I went behind the speedometer and pulled the connector for the oil light and polished the tab and pushed the connector back on. Yay, light.
However I soon found that both the oil and generator lights stayed on when the engine was running. Even more, the oil light stayed on even when I pulled the wire from the sensor. Also it seems the lights are both overly bright.
I figure I somehow shorted a hot wire into the system.
I'm confused. Any help here? Appreciated for sure.

Joseph

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asiab3
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Re: Idiot lights won't go off

Post by asiab3 » Fri Jun 12, 2015 6:59 pm

In a nutshell, the lights are always receiving power and the components in the engine are the grounds. This means:

1) The oil pressure sender grounds the oil bulb when pressure is low. If pressure is high enough to lift the ground, the light goes out. To test, with the key on and engine off, have a helper watch the light while you remove the wire from the oil pressure sender and ground it on something metal. Decklid latches usually work well, because there's usually a spot of bare metal where the paint is worn off. Grounding the wire should turn the light on, lifting the connector should turn the light off. If the light is always on, then the wire is grounding itself somewhere upstream. If the light lights and shuts off with grounding/ungrounding, your sender is probably faulty.

2) The voltage regulator grounds the G light bulb when the generator sin't spinning. When the generator is producing current, it's putting 12v on both sides of the G bulb, so there's no + and - current flow, so the bulb turns off. Again, if the light stays on as you ground and lift the #61 blue wire to the voltage regulator, there is a grounding happening upstream of the voltage regulator.

Are you sure you got all your instrument cluster wires hooked back up correctly?
Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

mentalQtip
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Re: Idiot lights won't go off

Post by mentalQtip » Sat Jun 13, 2015 1:33 am

Robbie, I would have sworn that I only removed the one wire for the oil sender. After studying the wiring diagram awhile and really looking at the colors of the wires I found that I had it wrong. The oil sensor wire and the high beam indicator light were reversed.(not working either).
All of the connections need cleaning/polishing badly.
So, again. You were right.

Thanks

Joseph

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asiab3
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Re: Idiot lights won't go off

Post by asiab3 » Sat Jun 13, 2015 7:20 am

So both the gen and oil light now function? Or have I misread the original post?
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

mentalQtip
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Re: Idiot lights won't go off

Post by mentalQtip » Sun Jun 14, 2015 11:27 pm

generator light still is troubling. That and the carburetor isn't able to keep it running/idling.

Joseph

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asiab3
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Re: Idiot lights won't go off

Post by asiab3 » Mon Jun 15, 2015 9:41 am

mentalQtip wrote:generator light still is troubling.
Did you have a helper lift and ground the #61 blue wire to the voltage regulator while you watch the light with the key on?
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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asiab3
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Re: Idiot lights won't go off

Post by asiab3 » Mon Jun 15, 2015 9:48 am

That and the carburetor isn't able to keep it running/idling.
I'm answering this in a separate post so if we need to move the discussion, to the fuel delivery or engine forum, we can.

We all have our opinions on what this could be, but I like to test, test, and test again. They're usually free, and you might even lean something… :blackeye:

Fuel, spark, and compression. Engines need them to run. (And that first sentence needs verb too, but who's counting…) Which one is the culprit?

If it drives halfway decent, we usually ignore compression issues if only the idle is struggling so we can focus on fuel and/or spark.

Always start with a basic tune-up: valves, then dwell, then timing, then carb adjustment if necessary. Pay attention during your tuneup: a timing light that is inconsistent in brightness or frequency could be a spark issue. Or a bad clamp on the light. Or something else. Details count, so be alert.

Family is calling, I'll be back to finish this…

Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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