Temp gauge rises when cold - Gauge/cluster working fine

[Mawrick 0]

What might cause the temperature gauge to rise directly when the ignition is on.

 

Earlier fixed a troublesome gastank level gauge on the same gauge - also the sensor is new.

 

The MFA seem to read correct temp though

 

 

EDITED this post:

 

As I'v found the cluster to be working OK - checked in another car, so if anyone know where this s**** get's it's signal from that would be of great help - or is there is some sort of resistance on the way from the temp-sender to the gauge?.

 

It actually seem to be rising a bit more once the car get hot - so it's starting out with a too high signal and then adds to it when it get's hotter......

[billy_whizz 0]

have you been playying with relays as when I fitted a relay in the wrong place this happened to me

[Mawrick 0]

nope - I haven't touched the relays :) - but can't remember if it was like this when I bought it (I don't think it was).....

[PaulMoVR6 0]

This happened to me but my gauge would shoot of the top of the scale, i eventually fixed it by changeing my dials and also replaceing new temp sender with the older yellow one instead of the newer black one which was already in the car.

[Mawrick 0]

Tried to disconnect the yellow temp sensor - but that didn't do anything, the gauge still raised up :(

 

Any other tips on what could be checked before I go out and buy a new one?

[Mawrick 0]

Any tips on this? - Any way to check/test the gauge itself?

[Critical_Mass 10]

Tried to disconnect the yellow temp sensor - but that didn't do anything, the gauge still raised up :(

 

Any other tips on what could be checked before I go out and buy a new one?

 

Surely thats the gauge at fault then. The yellow temp sender gives the reading to th clocks, so if you unplugged it and the needle still went up, then it can only be the clocks that are at fault.

[Mawrick 0]

Any idea what might cause it - I did a fix on the fuel gauge (same gauge), and that part of it works now, before it sat to 0 all the time....IIRC it was some bad wiring on it.

 

Is the temp gauge also possible to fix?

[Critical_Mass 10]

Any idea what might cause it - I did a fix on the fuel gauge (same gauge), and that part of it works now, before it sat to 0 all the time....IIRC it was some bad wiring on it.

 

Is the temp gauge also possible to fix?

 

Not sure mate. Each gauge is seperate from the rest of the cluster, so you could get another temp/fuel gauge and try it. But that depends weather its the circuit board itself is at fault or not.

[Mawrick 0]

yea, I'l check with the cluster I have in the Passat VR6 - it's not the same motometer/VDO, but they are interchangable :)

[Mawrick 0]

hmmmmmm - I'v now tested the cluster in my Passat - and it seem to be working fine.

 

Also the Passat cluster (wich I know is working) rises up the temp gauge in the Corrado.

 

To me it seem like pin 23 (AFAIK) on the cluster harness goes up to roughly 15-6mA on the C - and the Passat rises to roughly 7mA (but that is when engine is about 70C's).

 

Anyone know where this pin comes from ? - is it routed via the ECU - and might the ECU be at fault?.

[Mawrick 0]

Bumping this one (with some additional info in the first post).....

[Gareth_16V 0]

If the gauge goes straight up it sounds like the wire that comes goes to the sender has a short in it. Might be worth checking that the wiring harness isn't chafing on something, and checking for continuity with a multimeter both to earth and to the gauge. If there's continuity to earth that's bad, if there's continuity to the sender that's good.

 

HTH

 

Gareth

[Mawrick 0]

bumping this again.

 

earth seem to be ok in the harness atleast.

 

what I'v found from doing some research on the Passat is as follows:

 

it seem to have much same resistance as on my Passat VR6, but when I turn ignition on the Passat it will have roughly 9V at the harness, and the Corrado will only deliver 6V .

 

 

AFAIK the cluster operates roughly around 9V so that make sense on the Passat - but I'm baffled at what might cause it too loose 3V on the Corrado.

 

Any tips apreciated....:)

 

starting to think someone have been looking for power for something else somewhere and hooked themselves into this feed....:( (haven't found anything yet though...:( )

[SamG40 0]

Did you ever sort this? Anyone else had this issue? I've got the exact same thing. Tried another set of clocks and they go straight up too and I've tried a different temp sender. I don't know where to start with the wiring.

[Wild-Animal 0]

If your temp gauge is going straight up then check your wire of where it connects to the sensor is connected and MAKE sure its not earthing out as if it is earthing out then the temp dial raises to the top of the gauge.

 

Also if you think it could be sensor is at fault then unplug the wire and see if the gauge still rises. I changed a sensor recenlty I had the wire unlugged but touching the engine block and my dial rose to the top of the gauge as it was earthed out.

 

The sensor is located below your dizzy cap there are 3 wires that go to 3 sensors, the sensors are all the same so you can swap the wires around to see if its a dogy sensor.

 

2 are for your ISV and 1 is for your temp sensor

[willyj1888 10]

i had the same fault in my car.open the round multi-plug on top right hand side of the engine and check for corrosion on the pin connectors. if you have green discolouration on pins this could be the source of your problem.im having the engine wiring loom changed in my car later this week, i,ll let you know if it cures it. If you find discolouration on your pins spray contact cleaner into both sides of the plug and open and close the plug repeatedly and hopefully this should inprove connections

[Mawrick 0]

i had the same fault in my car.open the round multi-plug on top right hand side of the engine and check for corrosion on the pin connectors. if you have green discolouration on pins this could be the source of your problem.im having the engine wiring loom changed in my car later this week, i,ll let you know if it cures it. If you find discolouration on your pins spray contact cleaner into both sides of the plug and open and close the plug repeatedly and hopefully this should inprove connections

 

Did you got it sorted? -

 

 

sorry SamG40, didn't see this post before now - but haven't had time to get it sorted yet myself so if any of you guys have sorted it please give tips - hopefully will have a new garage up before the winter so I can sort the car out over next winter (it have been stored away at some other place during winter the last years so couldn't work on it then - and the summer is "driving time" :) ).