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Discussion Starter #1
When I turn the key prior to starting..... the oil/gen light come on but I don't see the temp light come on. Bulb is good, green wire from bulb to sensor has continuity, ground at lamp good. Doesn't all 3 lights suppose to come on prior to starting?
63 Chevy II with 194 6 cyl
 

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We might have to wait for a more specialized 63 owner to chime in but in the mean time if the car is stock and original then I have to think that when the key is turned to the "RUN" position the TEMP light may or may not be on depending on the temperature the sender is seeing. If the engine is stone cold, then with the key in the "RUN" position then the TEMP light should be off but if the engine is hot enough to trigger the sender to connect to a ground, then with the key in the "RUN" position, the light would be on. Once the motor is cooler than the trip temperature level of the sender, the light should go off OR possibly in the transition from hot to cold have the TEMP light go from full brightness to dim, then off. I've had this happen in my 68 before and nothing was really wrong except it was from being at a show crawling along and the outside temperature was close to 100 degree's out and the sender was not acting like an On/Off switch but instead varied a resistance to vary the brightness of the TEMP light in the dash.

I do know on my 68, and this is why you might have to wait for a more specialized answer pertaining to a 63, is GM built into some ignition switches a test circuit in that when the car was cranked over the sender wire for the TEMP light was put to ground to illuminate it and then once in the RUN position this ground was lifted at the ignition switch to turn on the light out and then relied on the sender becoming grounded before the TEMP light would come back on.

According to a diagram I have for a 63 it looks like your car should have the self test circuit for the TEMP light but I have had to question before some of the diagrams I have:



Jim
 

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Hi although I have an SS with gauges. I know the schematics and the 63 Nova very well I have mine 40 years. Did you try a different bulb? If yes,Check the contituinty between the ignition switch and temp light. If contituinty is good. Test for power behind the socket (socket could be bad) Socket should be grounded also when testing According to the schematics it should test just like the others
 

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With the key on simply ground the wire going to the sensor and the light on the dash should light. If it does the circuit continuity is good if not start checking.

Since these are a simple single wire grounding circuit, the dash light will not light until the temperature threshold is met probably @215 degrees. The short answer is the light will not come on while cranking. That is unless the coolant temp is above that threshold temperature.

Hope this helps....
 

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Discussion Starter #6
Temp light

Awesome, i will check the wire at the sending unit to ground to make sure the light works. Thanks all answered my question!
 

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Discussion Starter #7
temp lite

yep with ignition on, grounded the green wire at the sending unit and bulb lites. Thanks so much. Want to keep the hardtop as much stock as I can but may have to install a set of trio gauges . Like to see whats going on instead of trusting lites.
 

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not a bad idea too use both ---

I have ' SW ' under dash gauges & still use all my idiot lights.

I even have my water temp light, plus a manual temp gauge, then, I have a "Moon Direct Fit/Liquid Filled (the larger style) manual read temp gauge mounted in my 'thermostat housing' .

Then, my 69 came from th' Factory w/ 3 row V-8 Radiator & 7 blade fan blade (HD Cooling package from the factory) …. and, I use all three.

#1 -- add-on dash gauges



#2 -- under dash gauges -- (with after market "gas gauge" ).



#3 -- look at the top hose area. You can also see the 'stock water sending unit , also hooked up (in the head -- for the dash temp light) .



#4 -- closer picture of "MOON water temp gauge -- mounted onto 'thermostat housing' .

[



Hope this may help ………… jim
 

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With the key on simply ground the wire going to the sensor and the light on the dash should light. If it does the circuit continuity is good if not start checking.

Since these are a simple single wire grounding circuit, the dash light will not light until the temperature threshold is met probably @215 degrees. The short answer is the light will not come on while cranking. That is unless the coolant temp is above that threshold temperature.

Hope this helps....
I agree with this. The oil and Gen light come on, because the engine only sees low battery voltage and no oil pressure. 2 reasons the lights come on. Water temp should only come on when its hot. So the engine isn't hot when cranking. No need for it to come on.
 
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