Red flashing light in water temp gauge

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the edmundator
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Red flashing light in water temp gauge

Postby the edmundator » Sat Apr 23, 2016 11:41 pm

Am I right in thinking the red light in the water temp gauge also has something to do with the brake fluid level? I seem to remember this from a mk2 Polo I had, so wouldn't be surprised if other VW models followed the same system. Or is it just for low coolant level?

The light on my GTX was flashing from cold (didn't go out after the first few flashes) so water temp was not a problem - and needle only up to the 1/2 way point by the time I finished my journey. A short while later I got back in the car and the light stayed off.


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Re: Red flashing light in water temp gauge

Postby Nate » Sun Apr 24, 2016 12:13 am

Brake fluid level warning is the same as the handbrake light, isn't it?

Does yours have the coolant level sensor fitted?


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Re: Red flashing light in water temp gauge

Postby GTXTRA » Sun Apr 24, 2016 12:23 am

It'll be sensor related Ed - as in the screw in sensor on coolant bottle could be a little bit loose or the wire is exposed - the mk1 does this occasionally and i've got a mini cable tie around the rubber plug cover to keep it from slipping off........

As long as temp is normal and the coolant level is fine then this will be the area to look at.


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Re: Red flashing light in water temp gauge

Postby the edmundator » Sun Apr 24, 2016 10:26 am

Right-o, I must have just been having another senior moment.

Once the exams are (hopefully) out of the way I'll be organising a full service/general mechanical once-over for this one anyway.


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Re: Red flashing light in water temp gauge

Postby accyimp » Tue Apr 10, 2018 9:10 pm

Similar problem - light flashes then stays ON - 1.6 mk1 gti 1981
Engine runs up to temperature, needle rises steadily as expected and then electric fan kicks in as expected, but the red light is still on.
The header tank/expansion tank (n/s near suspension tower) there is no provision for any electrical connection - although in the area there is a 'redundant' two pin electrical connector (green/yellow and a brown) which is cable tied out of the way.
Any ideas? should there be some sort of sensor on the tank or elsewhere?
Thanks in advance
Andy.



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Re: Red flashing light in water temp gauge

Postby mark1gls » Tue Apr 10, 2018 9:27 pm

There is a relay on top of the fuse box as well which controls the light.

More info and help here.

https://vwgolfmk1.org.uk/forum/index.ph ... g-light-in


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Re: Red flashing light in water temp gauge

Postby blakey » Wed Apr 11, 2018 6:49 pm

It may be worth bridging the the pins in the plug as a test to see if that puts the light out. It would then suggest the wrong tank has been fitted (without provision for the level sensor). The sensor is effectively bridged by the coolant when at the correct level, if the level drops too low the the two pins are exposed and bring the warning light on.


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Re: Red flashing light in water temp gauge

Postby accyimp » Thu Apr 12, 2018 8:43 pm

blakey wrote:It may be worth bridging the the pins in the plug as a test to see if that puts the light out. It would then suggest the wrong tank has been fitted (without provision for the level sensor). The sensor is effectively bridged by the coolant when at the correct level, if the level drops too low the the two pins are exposed and bring the warning light on.


Tried that - temp needle just goes straight to top of scale when ignition goes on.
Cheers



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Re: Red flashing light in water temp gauge

Postby accyimp » Thu Apr 12, 2018 8:44 pm

mark1gls wrote:There is a relay on top of the fuse box as well which controls the light.

More info and help here.

https://vwgolfmk1.org.uk/forum/index.ph ... g-light-in


I'll check that one tomorrow - Thanks.




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