[hellblezer]

heey guyz,

how are you all, hope things are good.
a couple of weeks ago i got a yellow alert that ma coolant level is low, i opened the cover of the coolant and i found the level is low.
i called the garage am dealing with and he told me to bring the car ASAP, thinking that there might be a leak.
i took the car to the garage and after a day he called me saying that there is no leak but the thermostat is faulty !!! Therefore you'll have to replace the water pump as well!!
i didn’t buy what he is saying + i read some topics in forum and i found that its sometimes normal to get a low level in coolant, just add some OEM coolant and keep an eye on the alert.

My question is the coolant level related to thermostat in any way??
And if the thermostat is faulty will the car still give me a signal that the engine is overheating.
And what happens if the thermostat is really faulty??

Thanks guyz, i know its a long story but i appreciate your help

[ENINTY]

I'm assuming the Arab version of the "325i Coupe" has the same N52 in-line six as the 2006 USA version. The N52 engine has a separate electric water pump and separate electronically controlled thermostat. The thermostat and water pump can be replaced independently from one another. If the thermostat is faulty it will trigger a Service Engine Soon (SES) light on the guage display because engine operating temperature is monitored by the OBDII emissions system (I'm also assuming Arab versions are OBDII compliant). If the water pump fails, the yellow engine overheating warning will display with a chime. If you don't pull over and turn off the engine, it will shortly show the warning in red.

I think your garage is BS'ing you. You just have low coolant and nothing more than that. There would be no correlation between a low coolant condition and a faulty thermostat. If the thermostat is faulty you'd have a SES light on and a fault code could be read with a scan tool telling you so. If the thermostat is faulty, it will only fail safe in an open condition and not overheat the engine.

I'd just get the coolant topped off and keep an eye on the SES light. Also, take it to another BMW garage and ask them just to scan the car for codes and see what comes up. Don't tell them anything about what the other garage told you, just ask for a scan. I'd bet there are some fault codes present that are unrelated to the thermostat anyway; there always is. The car can have fault codes stored in the various control modules and not trigger the SES light.

[IFX]

if you top it up once, and the light comes on again (in which case you would check)

if it is low again, you have a leak.

Ask me how I know..

[hellblezer]

Originally Posted by ENINTY

I'm assuming the Arab version of the "325i Coupe" has the same N52 in-line six as the 2006 USA version. The N52 engine has a separate electric water pump and separate electronically controlled thermostat. The thermostat and water pump can be replaced independently from one another. If the thermostat is faulty it will trigger a Service Engine Soon (SES) light on the guage display because engine operating temperature is monitored by the OBDII emissions system (I'm also assuming Arab versions are OBDII compliant). If the water pump fails, the yellow engine overheating warning will display with a chime. If you don't pull over and turn off the engine, it will shortly show the warning in red.

I think your garage is BS'ing you. You just have low coolant and nothing more than that. There would be no correlation between a low coolant condition and a faulty thermostat. If the thermostat is faulty you'd have a SES light on and a fault code could be read with a scan tool telling you so. If the thermostat is faulty, it will only fail safe in an open condition and not overheat the engine.

I'd just get the coolant topped off and keep an eye on the SES light. Also, take it to another BMW garage and ask them just to scan the car for codes and see what comes up. Don't tell them anything about what the other garage told you, just ask for a scan. I'd bet there are some fault codes present that are unrelated to the thermostat anyway; there always is. The car can have fault codes stored in the various control modules and not trigger the SES light.

thaaaaaaanx man your reply was very well explained and usefull

[hellblezer]

Originally Posted by IFX

if you top it up once, and the light comes on again (in which case you would check)

if it is low again, you have a leak.

Ask me how I know..

i guess u had a leak problem in your car

[edelossantos]

Same thing happened to me last night. My 335i has been working fine and then last night when my wife and I were ready to go out to dinner, the low coolant warning came on after I started the car. No visable leaks in the garage or in the engine compartment. I took a look inside the coolant tank and it was really low. I went to my BMW dealer today as their parts department is opened on Sunday and picked up a gallon of coolant and some distilled water. I topped it off and made an on-line appointment with the service department to check things out.

[edelossantos]

I had my car in the dealer over the weekend and they did a pressure test and they could not find any leaks. They did a top off and I guess I will have to monitor this. While my car was in, I told the SA about some noises with the front brakes and they ended up replacing the brakes and rotors.

[acdHQK713K]

My coolant is disappearing also. No visible leaks that I can find. Dealer did a pressure test and could not find a leak.

I've lost about 1/2 quart of coolant in a month. Seems abnormal to me