KE30 Water Temp Sensor Diagram (4A-GE)

[PBaines]

Hey team, am wondering if someone has a diagram or can explain in detail how the temp gauge from the old KE Corolla's (I have a KE30/KE55) work?

I have done a 4A-GE 16v conversion and have just put a 4K temp sender so that the dash gauge will work. The car cam with an aftermarket water temp gauge but looking at getting the old one going.

I have found the Water Temp wire, It outputs 3.2v +- .1v. Though when i plug that onto the sender the gauge doesn't work. Am I missing something? I thought that since the water temp wire connected to the sender should get it going.



Have all ready done a forum search and yielded nothing relevant to my query
Cheers

[crowncustom]

Easy to see if the gauge works.Just get the temp wire and earth it out while you have the ignition turned to on.
Cheers Brett.

[Cuzzo]

I retro fitted the stock temp sensor to the 4age. Worked great.

[PBaines]

Cheers for that, yeah I have earthed it and the gauge went right up.
Bit strange though because when it is plugged into the sender nothing shows on the gauge. I know it is definitely a 4K sender.

I also retro fitted it, the 4A-GE had probably an M8 thread so had to drill that out and tap it to M16 to make the old sender works

[Hen]

Could it be that the sensor is stuffed or not grounded properly? If the gauge works then try grounding the sender body, putting the tip in boiling water and seeing what happens.

Hen

[PBaines]

Interesting turn of events.

I thought that maybe the thermostat was a bit iffy as I had to modify the water setup. The thermostat bypass between the inlet/outlet housings (engine side) pipe between them were rusted and could not source one so I welded them over and drilled 2 2.5mm holes through the edge of the thermostat to allow minimal flow through it. Turns out that was too much!

After replacing the thermostat with the little pinhole on the plate the engine heats up and the gauge works. Though the radiator I have in the KE30 (from a commodore I believe) is far too big. When I am driving at 100km/h the engine cools down so much the heater barely puts out any heat lol.
Max the gauge goes up in town (with no fan even) is 1/4 of the way up.