[72SSL48RAG]

Hey guys..got another question: I have idiot lights on my 72:
Is the temp light supposed to go on briefly
when you start the car? My Gen and Oil lights do. I think it should. I have a damaged PC board on the opposite side of the
Temp Gauge by the Gen Light..but that works..
it only affected my driver's side blinker...maybe they are on the same circuit?
With the exception of that blinker out everything else appears to be working.
What do you think...thanks.

 

[Coppertop]

On an old Chevy, the lights work (idiot lamps) like this:

When turning the key to crank the engine, the GEN lite comes on. This should go off as soon as the engine runs. The alternator has to spin fast enough to generate enough current to cause the voltage regulator's charging relay armature to pull down, thus turning the light off.

The HOT lite comes on when you turn the key as well, the ignition switch circuit temporarily grounds the light making it come on to ensure it is NOT burned out. A burned out HOT lite would be devistating as you would not know if your engine was overheating. This was done as a preventative measure.

The OIL lite will also illuminate until the engine runs and enough oil pressure is built-up to force the oil sender to un-ground, turning the lite off.

 

[Coppertop]

Concerning the driver's side blinker...

What's wrong with it? Is just the little indicator bulb not work, or do your blinkers literally not work right???

 

[72SSL48RAG]

The blinker stopped flasing when i damaged the circuit board. i pulled the light out and it looks good but ill try a new bulb anyway....

If the temp light is not coming on at all
and the light looks goods is there anywhere else I should check?
I need that gauge working..dont want to toast that engine.

thanks

 

[John_Muha]

Joe, Glad you are around. Sure been quiet. Studies keeping you busy?
On the 72, there is a contact in the ignition switch that does nothing more than make the temp light come on. Noticed one day my 72 was acting up. Found everything working ok except for the stupid light. If that sounds like what's going on, change the ignition switch. They are available over the counter.

 

[72SSL48RAG]

Thanks guys for all your help...it was a combination of a burnt light and poor contact on the base where it mounts (due to rust)..love those ragtops.

Thanks again