Wiring a new temp guage.

[Pabloek]

Sorry yes the fan guage in the engine bay is accurate and the fan kicks in at 85 as standard pre set.. It's the guage I fitted under the dash that's showing about 12 degrees cooler... The fan comes on a bit but if cruising it comes down as normal and switches off when it drops down etc.. No issues there. (it does heat up a bit more than normal when doing freeway speeds though, but as soon as I drop down to 80 km/h it regulates itself back down to normal etc, but that's a separate issue.. )
Just not sure why the dash guage is showing 12c under where it should be...

[Blacky]

weird - if its getting correct voltage to the gauge you would expect them to be reading pretty much the same

Can you get your hands on a temperature gun and see what it says to compare the 2 ??

[Errol62]

Should not be coming on at speed.

These are a cheap easy tool that can help diagnose heat related issues.
Point at top radiator tank. Hopefully it is black. Hose may read a bit lower due to rubber being an insulator.

The fan on my wife’s FB is turned up full. It only comes on going slow up hill or when stationary.


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[Harv]

My bet would be in the wiring. A temperature gauge is just a fancy variable resistor. As the sensor temperature changes, so does it's resistance. If one lot of your wiring has a large resistance (poor connection, loose, dirty, wire waaaaay too small) then it will provide resistance to the circuit, making the gauge read with an offset.

Cheers,
Harv

[Pabloek]

20241228_150030.jpg (1.98 MiB) Viewed 110 times

Hi guys I bought an infrared thermometer. I'm getting 3 different readings... It's killing me.... Just had it idling after warming up.. First three pics are taken straight after each other.. Guage under dash - 68. Guage near thermo switch - 83 and thermometer near top of radiator on the fins 91.5...?
Last pic was when thermo switch guage was about 85.. Engine block got to 103..
Havent looked at guage wiring yet...

[Pabloek]

Sorry pic order got mixed up, but you get what I mean..

[Errol62]

That clarifies that the dash gauge is the outlier at least. Where do you have the sender for that gauge situated?


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