Hello everyone

I have been getting the check coolant message for the last couple of weeks and was about to change the reservoir as is recommended on this forum.
However I have been going through all the receipts and found one for its replacement about 14,000 miles ago. I have to add that it looks very clean and new.

Before I change it what other faults could be the cause of the message or is this a normal length of time for it to last?

Thanks
David Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

It can be triggered by a low mix dilution. Needs to be at least 50% water and coolant or stg like that.

Might be worth checking the coolant level sensor which plugs into the bottom of the expansion tank. The last time I had a job done on my SC the mechanic forgot to reconnect it and I was getting similar messages. 2006MY 4.2 SC
BMW R1250 GSA Rallye TE
Triumph Tiger 1050 (sold)
1979 Pontiac Trans Am (sold)

Sorry, I should have said the fault is intermittent!

So guess it is connected but of course worth checking if its loose, so thanks.

I thought the strength of the mixture had been ruled in many previous responses to this fault, I cant see how a simple float switch could be sensitive enough but again I will check the specific gravity to check. Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

Last edited by bigbo on 20th Mar 2020 12:38am. Edited 1 time in total

I used to get this, about half a mile after leaving home, and then it would just disappear and not come back again. When it went in for a service last August I mentioned it and the local Indy told me that it was low so they topped it up with water. Message went away and I though no more of it. Last week it came up again, at the same point of the journey, and once again promptly went. It's now happening like that almost every time I go out.

I assume there's some sort of check once the temp gets to a certain level ? Although I've tried leaving the car running for 10 minutes and it still happens at the same spot. I almost started thinking it was doing a check after travelling a certain distance !

Interesting, mine is a little bit more random, sometimes immediately on start up, most of the time after 5 or 10 minutes and sometimes after a 1/2 hour journey. But it only happens once on a journey and not on every journey.

Once I have checked the items I mentioned previously I will keep a closer eye on it and log each time it occurs. Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

Dolphinboy wrote:

It can be triggered by a low mix dilution. Needs to be at least 50% water and coolant or stg like that.

Thanks, that's my understanding as well, but I will test anyway to make sure my concentration is good.
The manual is clear that the specific gravity should be 1.068 to get protection to -40c, I don't think any float could detect between that and 1.000

regards Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

“This is not true, the sensor is a magnetic reed switch and its not in contact with the coolant.”

Correct and incorrect, yes the reed switch is not in contact with the coolant but the float rides at a different level depending on coolant/water mix ratio.... so if your coolant mix is wrong <50% it will show as a low coolant on the dash.

Nino-Nino did a bench test to prove conclusively that you get low coolant alarm when filled with water, but not when 50% antifreeze is added.
Mike. G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

bigbo, check this post
https://www.fullfatrr.com/forum/topic43284...k+cleaning 2012 TDV8 Black Edition
2000 Disco. TD5
1975 series III

Thanks, I had seen that post but a useful reminder

I have lost my SG tester, so have a new one on order, due to arrive on Monday so will test my coolant and then decide on the next steps. Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

Having recently replaced my alternator, I lost pretty much all my coolant.
Prior to this I had been getting spurious "low coolant" warning, in the same way as the TPMS spurious warning, so I turned off the warning through the IIDtool car config options, vowing to keep a close eye on it.

When I refilled the system with 50/50, I re-enabled the warning and it hasn't re-appeared, so I'm assuming it was a dilution issue and not a quantity issue. Got - 2017 SDV8 Autobiography in Loire Blue
Had- 2008 TDV8 Vogue SE in Java black
Had - 2007 S/C in Stornoway Grey

Dolphinboy wrote:

It can be triggered by a low mix dilution. Needs to be at least 50% water and coolant or stg like that.