The guy who built my wiring harness for my Elite 2500 did not include a wire for the coolant level sensor. I was not thrilled about it, but did not think much about it. Fast forward, after installing the harness my coolant light/buzzer will not shut up.

The obvious answer would be to ground the wire on the harness, if this were a stock car. BUT since this is not a stock car I see two options. 1) Completely remove the F100 buzzer box. I am NOT a fan of this as I personally like the buzzer. it lets know when to up shift. It gives character to the car, and lets me focus on the road not on the tach. 2) Ground the brown and white wire at connector X12, that the coolant level wire would have eventually made its way to if it were not deleted.

I like option two better, but it got me thinking... Why not just re-enable the sensor? I have rebuilt two engines due to coolant seal failure. It is a known problem in these cars. The level sensor can save your engine and components from a lot further damage. So how would I reinstall the sensor? Could I splice it in to the brown and white wire coming off X12 or is there more to it than this? Does the ECU even control the sensor?

Here is a thread I am pulling some of my information from. Thanks for reading my ramblings. https://www.rx7club.com/new-member-r...estion-956655/

 

Another method..... since you have the 2500 you can put a low pressure pressure sensor (0-25 or 0-50) in your cooling system. Should your cooling system reach a point where it would trigger the factory sensor, more than likely your coolant pressure will have exceeded "normal". You can set up your safety strategy and all that with the haltech of course. Easy stuff.

if you wanted to do the factory method then it would be simply reinstalling the sensor and running it to the brown/white wire on the x12 connector. The ecu isn't part of the low coolant level circuit.

 

You just need to connect the sensor to the front harness, which is what the OE emissions harness does. We include a short, single circuit “harness” that makes this connection with the engine harnesses I build. You don’t need to run all the back to the X12. Just from the sensor to the front harness connector near the power steering pump. PM me if you need the connectors to build you own or want to have one made.