Technical Temp gauge wiring

[Bnmtuning]

Hi guys. Put a temp gauge in my seicento the other day, it works, but doesn't read the correct temperature. The gauge itself has 3 wires, negative positive and one for the sensor.

Maybe the wire I used for the sensor is too thick? As if I'm correct the heat transfers up the wire and into the gauge somehow I havnt a clue how to set it up right any ideas? Thanks

 

[Ziggy122]

Most temperature sensor work on Resistance

More specifically Negative or Positive Temperature Co-efficiency

Ie Positive IIRC is As temperature increase so does the resistance
Neg is Decrease in resistance as temperature increase

Ziggy

 

[Honeymonster]

It makes no difference whether it's PTC or NTC it sounds like its been wired correctly.

+ to a switched 12 volt feed

- to ground (or negative)

s to the sensor (one cable also to ground on a two wire sensor)

My guess would be one of the following three things:

1. I take it you used the sender (sensor) that came with the gauge and have positioned it in a sensible place? Unless it's a two wire sensor it's essential the outer casing is well grounded so stuff like PTFE is a no no.

2. You have the correct 12v feed and a good ground on the gauge itself.

3. If none of the above most likely your gauge or sender is faulty.

And what kind of wrong temperature are are talking here? anything between 70 and 95 is quite normal.

 

[fingers99]

Is this any help?

 

[Bnmtuning]

Thanks for the replies. Everything is wires up as it should, the temp is reading around 60 give or take but nothing more. Now there's a little screw on the adaptor (on the hose) and I'm going to try & ground this and see if that helps. Best way to route wires through to inside of car?

 

[fingers99]

Best to use existing wiring routes/grommets. There's one on the passenger side of the engine bay, one right below the battery shelf.

 

[Honeymonster]

Thanks for the replies. Everything is wires up as it should, the temp is reading around 60 give or take but nothing more. Now there's a little screw on the adaptor (on the hose) and I'm going to try & ground this and see if that helps. Best way to route wires through to inside of car?

If you're using an inline adaptor it's absolutely essential you ground that screw. Normaly the sender wold be grounded by the engine block, in a pipe adaptor the rubber hoses isolate it.