Low coolant warning light.

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HenryM3
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Post Mon Nov 16, 2020 6:54 pm

Level is ok light is on the check panel. Have removed the level sensor and lifted the float. No change. What is the correct way to check wiring or float. Have disconnected plug from float and light remains on. All help much appreciated.
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Satan
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Post Mon Nov 16, 2020 7:35 pm

I think you can stick a piece of wire between the pins and the light should go out as I think I did this with my sons car, in the end it was a faulty float valve.
HenryM3
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Post Mon Nov 16, 2020 9:52 pm

Thanks will try tomorrow
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Post Mon Nov 16, 2020 10:13 pm

New ones are cheap, treat yourself,
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Brianmoooore
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Post Sat Nov 21, 2020 11:01 am

Satan is correct. Short the pins and light should stay out.
There is a reed switch inside the stem of the sensor, with extremely fine wires connecting to it. Eventually, coolant seeps into the stem and corrodes through the wires.
The other common possibility is an internal break in the wiring to the plug, right where it enters. This can be intermittent, and pulling the plug off to short the pins might cause a temporary repair, so pull gently at each wire when the shorting link is in place.
HenryM3
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Post Sun Nov 22, 2020 2:08 pm

Done the recommended checks, duff sender so just need to replace. Can’t whine about a 30 yo part that needs replaced.
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Satan
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Post Sun Nov 22, 2020 6:45 pm

HenryM3 wrote:
Sun Nov 22, 2020 2:08 pm
Done the recommended checks, duff sender so just need to replace. Can’t whine about a 30 yo part that needs replaced.
I believe there are two sensors so go with Cotswolds and you VIN number to get the correct one.
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Brianmoooore
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Post Sun Nov 22, 2020 6:48 pm

Satan wrote:
Sun Nov 22, 2020 6:45 pm

I believe there are two sensors so go with Cotswolds and you VIN number to get the correct one.
There are. One fits with the terminals at the top, and the other fits with the terminals at the bottom. The latter one has a slightly longer stem than the former.