[BashShah]

2012 335i Sedan - Sportline Model with approx 115K km. (canadian)
ok, brief history.
had a hit in run in the front of the car.
Bumper, Headlights, Rad, AC Condensor, Rad support, and hood were replaced under insurance.

Even in it's banged up state, no errors, all lights worked, and no leaks of any kind. drove it for over 1.5 hours to reach the bodyshop and no issues.

I upgraded to m Sport Bumper.
Picked up car on Dec 30th it had a Low Battery warning but it started just fine.
About 15 mins away, Low Coolant message, and it started blowing cold air in the cabin..... I slowed down, and parked 1 min later.
Oil Temp went slightly past halfway mark.
Owner of Bodyshop brought 3 liters of more coolant with him, and the car took it all.
At that point, he had it towed to his shop and I went home.
Next day Dec 31st, culprit was found, lower rad hose popped out as it was not clipped in 100%.
Now they did a Vacuum purge and sucked out the air.

I performed a Bleed Procedure via max temp, and hold gas pedal down for 10 sec.
the problem I saw was, that the purge ran for 25 min...(I timed it.)
and unless I stop it by shutting car down, it just kept going, would not stop.

Drove home, no issues, Drove everyday and no issues, till today I got a low coolant warning.
got home, checked it, coolant was half way of expansion bottle.
filled it to the top, ran another bleed procedure, and again, bleed procedure would not stop again....this time, I ran it for 30 min. hmmmm

I still have a low coolant warning and it won't go away.

any help would be greatly appreciated.
Thank you in advance.

[BashShah]

hmmm 87 Reviews and No responses.
Update:
Car Sat for 2 hours.
Then went to car, and there was no indication of Low Coolant warning.
Performed another Coolant Bleed Procedure.
This time it stopped at the 19:46min itself.
All this was on the 3rd.

Now the 5th night and no issues.
hmmm......

[Billfitz]

I'm assuming the body shop didn't perform the bleed procedure, which requires special gear to perform.
https://www.newtis.info/tisv2/a/en/f...check/CNCeB76L

You can't hand a BMW to anyone and expect that they know how to work on them. It's not your father's Oldsmobile.

[zinner]

You don't need any special gear to bleed the coolant system. I have changed out the aux rad and flushed the system with no special tools. There is a special procedure to get it to purge air without running, sounds like you know that one already.

That said the low coolant switch is in the overflow tank I believe. It could be that sensor has a bad connection or has failed. I think it runs of some electric property of coolant itself and not the level. It might be a non bmw coolant in there that doesn't play nice with the sensor. Pentafrost NF and distilled water will work with that sensor in the F30 tank.

[BashShah]

Originally Posted by zinner

You don't need any special gear to bleed the coolant system. I have changed out the aux rad and flushed the system with no special tools. There is a special procedure to get it to purge air without running, sounds like you know that one already.

That said the low coolant switch is in the overflow tank I believe. It could be that sensor has a bad connection or has failed. I think it runs of some electric property of coolant itself and not the level. It might be a non bmw coolant in there that doesn't play nice with the sensor. Pentafrost NF and distilled water will work with that sensor in the F30 tank.

Thank you, it was the Tank Sensor, and yes they did not use OEM Coolant.
Plan on draining it and refilling it with good stuff when the weather gets better.

Thank you for the reply.

[kahnfucious]

I would wait too long on the coolant - incorrect coolant can cause all kinds of problems long term. Switch it out now

[BashShah]

Originally Posted by kahnfucious

I would wait too long on the coolant - incorrect coolant can cause all kinds of problems long term. Switch it out now

Did it the Next Day.
and Flushed it also.