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  #1  
Old 27th June 2022, 08:05 AM
Mossyboy1978 Mossyboy1978 is offline
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Default Temp warning but no overheating

Morning all

I keep getting regular temperature warning - the big red thermometer in the centre of the dashboard! - but the car is ALWAYS rock solid at 90 degrees. It's been happening for a about a fortnight and I've driven to good wood and back with the warning light flashing but the car was beautiful and never skipped a beat.

Could it be the sensor in the coolant tank?

The coolant level is fine.

Thanks

Mossy
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  #2  
Old 27th June 2022, 10:42 AM
ainarssems ainarssems is offline
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Yes, that warning is for coolant level not for temperature
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  #3  
Old 15th September 2023, 08:13 AM
Mossyboy1978 Mossyboy1978 is offline
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Bumping this up again as I'm get fed up with the warning and cannot find a new tank with a fresh sensor in it anywhere. There is defo not a coolant leak or issue.

If I just disconnect the sensor will that stop the warning or make it keep going as it cannot sense any coolant at all?

The beeping and icon are doing my head in...
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  #4  
Old 15th September 2023, 09:16 AM
MikkiJayne MikkiJayne is offline
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The V6 part is basically the same as the V8 one but with an extra bracket that has no effect on anything.

https://www.autodoc.co.uk/car-parts/...N%204D0121403C

https://www.ebay.co.uk/sch/i.html?_f...c&LH_PrefLoc=1
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  #5  
Old 15th September 2023, 09:23 AM
Mossyboy1978 Mossyboy1978 is offline
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Brilliant! Thank you.

And disconnecting the sensor wont make any difference?
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  #6  
Old 15th September 2023, 09:56 AM
MikkiJayne MikkiJayne is offline
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Disconnecting the sensor is the same as low coolant. You could try shorting the pins on the connector to shut it up while you order a replacement.
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  #7  
Old 26th September 2023, 03:45 PM
Mossyboy1978 Mossyboy1978 is offline
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So now I am really confused.

Autodoc sent me two new coolant reservoirs by accident instead of one. Hooray!

Installed first one and the same warning comes on about 10 seconds after ignition. Considered it could be a dodgy sensor in the tank and so installed second one. SAME THING happens!

Checked sensor plug wiring and all connected up properly inside the connector. No rust etc. All tidy.

Checked sensor plugged into connector the correct way and it is.

What on earth could be causing this to keep flagging an alert if it isnt the connector or the sensor in the tank??
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  #8  
Old 26th September 2023, 07:31 PM
Ronin Ronin is offline
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Did you test the sensor wiring?
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Old 28th September 2023, 08:55 AM
Mossyboy1978 Mossyboy1978 is offline
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I haven't actually. I need to get a voltmeter and see if there is current.

Question is - if there isn't, where does that wiring go back to that might need to be checked? Fusebox? ECU?
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  #10  
Old 28th September 2023, 01:39 PM
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steamship steamship is offline
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Quote:
Originally Posted by MikkiJayne View Post
You could try shorting the pins on the connector to shut it up while you order a replacement.
Quote:
Originally Posted by Mossyboy1978 View Post
I haven't actually. I need to get a voltmeter and see if there is current.

Question is - if there isn't, where does that wiring go back to that might need to be checked? Fusebox? ECU?
Have you tried MJs suggestion of shorting the pins on the connector? i.e. short pins + warning disappears = wiring okay
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