Temp gauge not working 1y engine, strange wiring.

[nikalele]

Hello everyone,

Okay, im confused. temp gauge not working at all, just sits at the bottom, doesnt move. Iv found a couple of topics on here about this but none of them seem to clear things up for me.

Iv tested the gauge by taking out the box number 43 on the fuse box and putting a wire between 2 of the sockets, the result showed that the gauge itself does actually work, it shot up to the top. that was good. i then went round the back to look for the temp sender, i found both the coolant level gauge and the temp sender had some dodgey wiring. infact it looked as though only one spade connector was connected to the temp sender on the coolant flange. i pulled it off to have a closer look. the wire connected to it was infact 2 wires connected together, a yellow one and a blue/white one. there was also a loose wire ( i think it was blue, or blule and black not too sure). anyway i had a go at connecting both of these wires to the sender to find that the sender had 4 prongs on it, this is where i got confused. I also tried testing for continuity in the sender, i found none (although im a bit of an amature, so i didnt really know if there was meant to be of not, thought there probably should be though). anyway, Any help much appriciated. I did read earlier about something to do with earthing this sender to make it work..?

Ah while im here, the guy i bought the van off was worried about oil pressure because the buzzer sometimes came on, so he put an oil pressure guage on. The guage seems to prove that pressure is being held so i want to take it off as its actually causing a slight leak. the gauge is screwed into the right hand side of the head (gearbox end). Does anyone know what was originally there? electronic sender? blanking plug? oil temp gauge? i have no idea. again any help or advice would save me a lot of head scratching

Thanks for reading

[nikalele]

just wondering if anyone knows if i can use this...

http://www.brickwerks.co.uk/index.php?p ... t&Itemid=6" onclick="window.open(this.href);return false;

because it looks as though you can insert a sender into one of the holes. not sure if this is correct. If so... sweet the wiring seems to be ok although im still a little baffled as to how to earth the sender and which wires to connect to it.

As for the pressure gauge fitted to the cylinder head. what was originally in this hole?? its just next to the water flange on the side of the head.

Thanks in advance

[devoncamperman]

Check the temp sender wiring, the switch has two wires one side should be earth, the temp sender is a resistor and gives a varied resistance to earth depending on temp. Make sure one side is earthed or it will never work.

On the cylinder head it would be a oil pressure switch, but a simple one that would switch on the light on the dash if there is no pressure.

Good luck

[sdelasal]

like an oil pressure switch here...

http://www.brickwerks.co.uk/index.php?k ... hop.browse" onclick="window.open(this.href);return false;

probably the blue one for the cylinder head on a diesel. steve

[devoncamperman]

This is right, this should be fitted to the cylinder head gearbox side.

[nikalele]

iv just managed to get hold of a metal flange from the original cs engine, bought a temp sender from brickwerks. hopefully not it will earth through the flange body itself.

Took the dash apart the other day to fix the speedo cable noticed a bloody great tear in the circuit. this could possibly be causing some issues. I have a feeling the fan hasnt been working since iv had it... could that be down the the PCB in the dash being ripped?

[devoncamperman]

If you mean the fan on the rad, then this will have no effect on this. The cooling fan is only opperated with the temp sensor switch on the rad it opperates independantly to the gauge.

[nikalele]

ah ok, makes sense. so to test the temp switch on the rad, what should my multimeter read?

[Prazeanbeeble]

i had same problem, if you do not use the metal flange from a cs engine (still available to buy from vw heritage), it will not earth and therefore not work!
this was the bit that caused me the most frustration.
but, i now have a KY engined van that has a plastic flange!

[devoncamperman]

I dont know the resistance, it is not a variable device but a switch, the way to check it is to put it in hot water and check continuity. it should be a two stage where at a lower temp will go s/c to one pin then at a higher temp will connect to the other. 2 stage speed for the fan.

I disagree with the metal flange giving an earth, on my engine it is plastic from Brickwerks, there is 2 pins on the sensor, one pin should go to earth, the other pin goes to the temp gauge, inbetween this is the sensor ie a variable resistor. This uses the earth and gives a different resistance to earth as to temp to the gauge.