I'm soon installing a new 3-core aluminum radiator in my 1985 4+3 Corvette. I noticed that the new radiator has a fitting for a low coolant sensor. I cannot find any wiring (green wire from what I understand) that would lead to that sensor anywhere. My current old radiator just has a plug of sorts to close that port on the radiator. I don't even think there is a warning light on the driver info center that would notify "LOW COOLANT LEVEL". Is it possible that an early 1985 did not have that function?

 

Your car I believe has likely had it's OE radiator replaced once or maybe more times.

I don't believe that any '85 would have had 'low level probe' function. It was added in '86 and there was no add package to install on later. If you add a probe to your new there's potential to add the function I believe. The later 'module' was used in several GM products. I don't know anyone that has added the function to an early C4 but I believe it would be doable.

 

You need the module.

Syclones and Typhoons have a "Low Turbo Coolant" light for the intercooler system. There is a probe in the IC radiator but no module was fitted. So the light did not function as-built. Back in the day, I retrofitted several SyTy with the module, and the light worked as intended. The module was still available over the counter in 1998-2000-ish. No way would it be available today.

Here's a copy/paste excerpt of the how-to I wrote in 2002.

 

Ironically, I'm in the same situation....and I can't help myself, I like upgrades...especially ones made by the manufacturer! I bought a DeWitt's radiator and it has the same provision for the probe...so I figured I would make it functional! It is in my pile of circuitry to add to my '84 (EBL Flash II, IAT sensor, Trans Temp gauge, AFR gauge, Fuel Pressure gauge, Passenger Power Seat and Switches, VKE-1000 Keyless Entry, etc.....) All of the above is great information! In the photos below you will see what I have collected for this circuit. I can tell you the information center (tell-tale) filter/lens is the same for '84 & '85 and then '86 & '87 are the same ('86 is the first year of "low coolant" light, as correctly stated above)...It just so happens that there is a light bulb hole in the earlier information center housing in the correct spot, but there is no contacts on the printed circuit board for this hole...this is a good thing, this makes it easy to wire it in independently, using a bulb socket with wires instead of contacts (example of a source for this, the gear indicator plate/housing light bulb socket & wires). I think it's cool to add stuff like this, and to know I'll likely have one of very few '84s with a "low coolant" warning light! If you're not interested in adding this circuit, I would suggest that you buy the correct probe anyway and use it to plug the hole...that's what it was designed to do as far as sealing that hole and holding up against leakage. Good luck with whatever you decide to do! For anyone in the future who might be researching this topic to perform this mod, hopefully these pictures and the part #s above help you out...I believe it is every thing necessary to complete the job👍


Probe pigtail sourced from Lectric Limited.

Sensor/Probe.

Factory module/wiring, sourced from Forum member AZSP33D...a super great guy!

Bulb socket pigtail for information center, sourced from an extra center console wiring harness I had in my extra parts bins.

Example of '84 & '85 filter/lens.

Example of '86 & '87 filter/lens. Notice all icons are in the same place as the earlier version (some icons changed visually, but are still for the correct warnings, and the security went from 2 spots to one) the only other difference is the addition of the "low coolant" and "anti-lock" This filter can currently be had from an eBay seller (no affiliation) for $19 + s/h/tax...search '1986 corvette information center lens'....something to that effect!