Generator and Oil Pressure Lights not working

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Dan Macdonald
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Generator and Oil Pressure Lights not working

#1 Post by Dan Macdonald »

Guys,
I recently had my '59 coupe's body work done and fully repainted.
When I got it back, the interior lights didn't work. Obviously, they painted over the area where the light switches on the doors ground so I fixed that last weekend.

But, the generator light AND the oil pressure light do not work. They worked before the body work started, the bulbs are good, visually the connections at the engine and the combo gauge are fine.
Is there some common ground, wire, whatever for these two lights? Any ideas why they both wouldn't work?
Thanks.
Dan Macdonald 
'59 A Coupe (105327) 
'57 Speedster (82954) 
Registry #1921 (1982) 
DMAIA@aol.com
My YouTube Channel: Tinmeister 356

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Wes Bender
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Re: Generator and Oil Pressure Lights not working

#2 Post by Wes Bender »

The generator light doesn't really ground. If you have a voltmeter/ohmmeter, I'd use it to chase the problem. The issue with both lights might be related or may not be.
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Mike Wilson
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Re: Generator and Oil Pressure Lights not working

#3 Post by Mike Wilson »

If I'm understanding this correctly, you had body and paint work done so were the gauges were removed? If so, I'd check the wiring from the ignition switch to the gauges. Are there any other gauge functions that aren't working: temp, fuel level, etc.?

Mike
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David Jones
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Re: Generator and Oil Pressure Lights not working

#4 Post by David Jones »

The generator light has power on one side until the generator builds up enough voltage to dim and then extinguish the light by overcoming battery voltage so has nothing to do with the oil pressure light, there is no ground connection. The oil pressure light is just a switch that is opened once the oil pressure builds and that can be tested simply by grounding the wire at the switch. Ground the wire and light comes on, lift the wire and light is out.
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Dan Macdonald
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Re: Generator and Oil Pressure Lights not working

#5 Post by Dan Macdonald »

Thanks guys,
FYI, the gauges were NOT removed for the exterior body work and paint.
David, thanks, I'll give that a try.
Mike, thanks, I'll check that as well.
Dan Macdonald 
'59 A Coupe (105327) 
'57 Speedster (82954) 
Registry #1921 (1982) 
DMAIA@aol.com
My YouTube Channel: Tinmeister 356

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Mike Wilson
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Re: Generator and Oil Pressure Lights not working

#6 Post by Mike Wilson »

Was the engine removed and were the lights working prior to the body and paint work? Would any of the body work compromised the wiring?

Mike
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Dan Macdonald
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Re: Generator and Oil Pressure Lights not working

#7 Post by Dan Macdonald »

Mike,
No, the engine was not removed. I don't think they would have messed with the wiring but I guess it's possible that they cut it or crimped it accidentally.
Dan Macdonald 
'59 A Coupe (105327) 
'57 Speedster (82954) 
Registry #1921 (1982) 
DMAIA@aol.com
My YouTube Channel: Tinmeister 356

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Mike Wilson
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Re: Generator and Oil Pressure Lights not working

#8 Post by Mike Wilson »

As Wes and David have advised, do a continuity check.

Mike
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Wes Bender
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Re: Generator and Oil Pressure Lights not working

#9 Post by Wes Bender »

Don't know if your car is the same, but using Joe Leoni's B & C schematics, it appears that both the oil pressure light and the generator light share a connection to the ignition switch. The oil temperature and fuel gauges also share that connection.

Do your fuel gauge and temp gauge work OK? If so, check the wire (possibly blue/yellow) between the temperature gauge and the warning lights. If the gauges aren't working, check the wire (also blue/yellow) between the ignition switch and the fuel gauge.

Power comes from the ignition switch terminal 15 and lands at the + side of the fuel gauge. From there it goes to the + side of the temp gauge and on to the oil pressure light and then to the generator light.

Hope that helps.... also hope the wire colors are correct. I suspect that something has popped loose and merely needs to be reinserted, but that's a WAG on my part.

Wes
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Re: Generator and Oil Pressure Lights not working

#10 Post by Mike Wilson »

Wes.That's what I was thinking as well...

Mike
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Re: Generator and Oil Pressure Lights not working

#11 Post by George Hussey »

I would check the red and white power lead to both and see if it is powering with the key on.
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Dan Macdonald
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Re: Generator and Oil Pressure Lights not working

#12 Post by Dan Macdonald »

Great advice guys. I'll get on it this weekend. Thanks!
Dan Macdonald 
'59 A Coupe (105327) 
'57 Speedster (82954) 
Registry #1921 (1982) 
DMAIA@aol.com
My YouTube Channel: Tinmeister 356

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