Every year when the temperatures drop we get alot of threads about coolant warning lights.
there are a few of reasons for this:
1. the colder the coolant temperature, the lower its level will be. This could lead to low level warnings.
2. the sensor in the coolant expansion tank to warn of low coolant level is basic in its design and very basic in its effectiveness so you can get false alarms.
3. a combination of 1 and 2
In short, two prongs stick into the coolant, i think the coolant acts as a conductor and therefore a link between the two. If the level drops then an alarm is given.
However the sensor prongs can also get dirty or simply less sensitive over time which might lead to false or premature alarms,. In conbmination with low temps lwe can expereince alot of false alarms.
Fixes:
1, easiest and works 9 times out of ten is to top up the coolant a bit so that when cold the coolant level sits toward to top of the range diplayed on the expansion tank rather than at the lower end of this range. (note when hot the coolant will expand and will therefore be above the max indicated, this is fine dont worry.
2., clean the sensor prongs.
3. give prongs a wiggle
4. remove, wiggle clean and basically do all you can to make sure all electrical connections are good.
and no the sensor cannot be replaced as its built into the coolant expansion tank. to replace its a new expansion tank.
Many people have done this, (and its the dealers fix) however it might happen again next year as i am not aware of any updates to this part and often its not the new part that fixes it its that fact when you refill the coolant you set it to a level higher than before.
Its the time of year we should all be checking things like coolant, and my tip is also to make sure the connect release works and its well lubricated. (worth doing a couple of times in the winter, particularly when the salt season starts. You dont want to find you cant open the bonnet...
there are a few of reasons for this:
1. the colder the coolant temperature, the lower its level will be. This could lead to low level warnings.
2. the sensor in the coolant expansion tank to warn of low coolant level is basic in its design and very basic in its effectiveness so you can get false alarms.
3. a combination of 1 and 2
In short, two prongs stick into the coolant, i think the coolant acts as a conductor and therefore a link between the two. If the level drops then an alarm is given.
However the sensor prongs can also get dirty or simply less sensitive over time which might lead to false or premature alarms,. In conbmination with low temps lwe can expereince alot of false alarms.
Fixes:
1, easiest and works 9 times out of ten is to top up the coolant a bit so that when cold the coolant level sits toward to top of the range diplayed on the expansion tank rather than at the lower end of this range. (note when hot the coolant will expand and will therefore be above the max indicated, this is fine dont worry.
2., clean the sensor prongs.
3. give prongs a wiggle
4. remove, wiggle clean and basically do all you can to make sure all electrical connections are good.
and no the sensor cannot be replaced as its built into the coolant expansion tank. to replace its a new expansion tank.
Many people have done this, (and its the dealers fix) however it might happen again next year as i am not aware of any updates to this part and often its not the new part that fixes it its that fact when you refill the coolant you set it to a level higher than before.
Its the time of year we should all be checking things like coolant, and my tip is also to make sure the connect release works and its well lubricated. (worth doing a couple of times in the winter, particularly when the salt season starts. You dont want to find you cant open the bonnet...
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