1966 300 Idiot Lights?????

[Hunyadi]

OK - Ive had my 66' 300 for about a month now and working thru the little details to get it "restored" (for lack of a better term) - I noticed that it has the standard "idiot" lights for Oil - Hot and then this one throws me for a curve "COLD" - its in green and right next to the "HOT" - what is that for! My only guess is linket to the temp sensor and if the block is frozen solid that will come on??? Anyone have an idea what that was for? Its also a non AC car so its not the "max AC" button indicator (like they had those in 1966....)

 

[polara71]

I have never seen one on a Chrysler. However my dad had a 67 Ford Galaxy and it had a "cold" light. You were supposed to let the car warm up before putting it into drive, in other words don't move the car until the cold light went out.

 

[300rag]

When the car is started cold, the green cold light will come on and stay on until the motor warms up a bit. If you look at the sending unit you will see it has two wires coming from it instead of the usual one wire.

 

[Hunyadi]

Interesting - yep it does have a two wire temp sensor! But the green "COLD" light does not come on. Porbably the bulb - thats all I've been replacing on this thing is bulbs - but thats not a bad electrical problem to have...

 

[Aquaman]

I have 2 68 Newports. The Cold light comes on, well, when the engine is cold. On a hot summer day it does not some times. Mine did not work until I replaced the sending unit. I am assuming (and you know what Felix said about assuming) that the sending unit was bad and both should work.
That all said, i am going to put a temp gauge under the dash as some point as I do not trust the "idiot" lights.

 

[BillGrissom]

I have the hot/cold sensor & light in my 65 Newport. They are still available since I replaced mine a year or so ago, perhaps www.rockauto.com. I think they were used by many manufacturers. In some ways it is superior to a continuous gage. The later are often very inaccurate, especially since they rely on the 5 V regulator which is notorious for failing (inside fuel gage in 65) and is better replaced with the electronic one (search ebay). A temperature switch is simple and accurate, assuming it works.

To check your wiring and dash, ground each of the 2 sensor wires (one at a time w/ ignition on). The green or red light should light. If not, your bulb or wires are bad. In the morning (< ~70 F), the green light should be on if the sensor is good. To check the hot switch you can remove it and put in boiling water, unless your engine already boils over, or you can try a heat gun or big soldering iron on it while it is installed (drain the coolant down past it).

The plastic connector housing often degrades from engine heat, as mine did. You can just use individual spade terminals on the two wires, with no housing. The only terminal housing I have found in auto parts is the 3 terminal one for headlamps, which can be made to work, or I think you can find a suitable 2 terminal housing in junkyards - look for interior ones from a 60's GM or Mopar. They are termed "56 terminals" or "Packard 56 terminals" (not from the automobile).

 

[jpj]

Yep, it just tells you the engine is not up to operating temperature yet. I have it on my '66 300

 

[CBODY67]

From my experience, the "COLD" light not coming on has seemed to be pretty common on our '66 Chrysler.

When the cooling systems on these C-bodies are in good condition, with a good radiator cap, good fan clutch, AND a clean radiator core (internally), there's very probability that the "HOT" light will ever come on during driving.

CBODY67

 

[67Monaco]

Bump. just for S&G's...

 

[commando1]

I'm glad you did. I'm going through all 132 bulbs in my dash as we speak....

 

[polara71]

I'm glad you did. I'm going through all 132 bulbs in my dash as we speak....

one hundred and 32 bulbs? hthedrama:

 

[67Monaco]

I think I'm going to go LED. The stock bulbs there now i can't really see on the brightest setting of the wheel.

 

[mgm1986]

I think I'm going to go LED. The stock bulbs there now i can't really see on the brightest setting of the wheel.

I believe LED is a little more tolerant to spikes compared to incandescent bulbs. Either way I would try to track down why all these bulbs blew. Is your charging system working correctly? Or is it a simple matter of bulbs blew over the life of the car and nobody ever bothered replacing?

Either way, good luck!

Info on LED voltage spikes:
http://www.philipslumileds.com/uploads/246/NA04-pdf

 

[commando1]

LED's run on Mystery Juice.
I don't install anything that runs on Mystery Juice.