Temp Light Flashing Red Soon As I Start The Car

[superted]

Picked up my new golf 1.8 16v on saturaday replaced a few parts, cambelt, water pump, dizzy unit complete and full service, and the only thing left to do is sought out my temp light as its flashing soon as i start the car and the needle goes straight into the red before the engine has warmed up does anyone have an idea what this could be.  ie faulty clocks or faulty sensor. One more thing the fan kicks in still so im puzzled.

Glenn

[nige_s]

I'd start by changing the temp sensor and it's wiring.

[rubjonny]

yeah that means the dash sender wire is earthed or sensor is bust. look for a red/yel wire to side of head, if its connected ok swap it to another one of the 3 sensors on the side of the head and try again. if solved, buy a new sensor
you dont want to drive it with the other sensor unplugged, as the other 2 are for the ecu and the isv controller. at least if dash sensor is bust it will still drive ok

[superted]

yeah that means the dash sender wire is earthed or sensor is bust. look for a red/yel wire to side of head, if its connected ok swap it to another one of the 3 sensors on the side of the head and try again. if solved, buy a new sensor
you dont want to drive it with the other sensor unplugged, as the other 2 are for the ecu and the isv controller. at least if dash sensor is bust it will still drive ok

checked wires changed the 3 connectors that go to, two sensors on the side of the head, which was a b/w wire and g/r. The other sensor was on the back of the head which was g/b couldn't see another sensor or a r/y wire.

[rubjonny]

it'll be on the engien somewhere, the correct location is on the side of the head. look all around the engine bay for a red/yel wire, its in there somewhere!

[superted]

it'll be on the engien somewhere, the correct location is on the side of the head. look all around the engine bay for a red/yel wire, its in there somewhere!

just had another look in the engine bay still no joy with this red/yell wire the onlt wire thats that colour looks like it goes to the earth on the gearbox bolt i have taken some pictures.

[rubjonny]

i can see a random wire near the starter motor in the 1st pic

[superted]

i can see a random wire near the starter motor in the 1st pic

No random ones ive checked all the wires coming out of the loom wrapping making sure that the wire hasn't broken and someone using a random bit to join it back up, with a different coloured wire. So that red and yellow wire with a black spade style plug i take it is in the right place and is an earth. 

And i thought my R5 was a pain in the backside you got to love these old cars 

[rubjonny]

that sounds liek the wire im on about, if it is red/yel then thats your dash temp wire, and if you earthed it to the gearbox then thats why the dash is shooting up to max

take it off, and check the dash again. if it doesnt shoot to max then theres your problem! get yourself another single pin black collar sensor and fit it to the spare hole in the side of the head if you dont already have a sensor there.

[MBChB]

If this is a 16 valver, what about the two-pin sensor underneath the flange going to the heater matrix (second picture)? It's virtually impossible to see with the flange in situ, but I had to fit a new flange a few weeks ago because of a leak and when I had it off I was pretty certain it was the temp gauge sender...though I might be wrong here?