electric radiator fan turns on high

[mexjim]

I have a 2008 328i e90 automatic. I've recently noticed the electric radiator fan turns on "high" speed(I can hear it) occasionally when going up a hill even on cool days(40-50F). I'm not talking about a long steep hill. It could be only a gentle incline and only a block or so long. If I stop at the top of the hill the fan turns off within a few seconds.


I have an OBD2 reader that allows me to monitor live ECT. When the fan turns on it shows around 180-185F.


I've also let the engine idle for about 10 minutes and watch the fan. It turns on/off "low" speed at about 180-185F.


My OBD2 reader only shows one ECT temperature. If there are multiple ECT temperature sensors monitored by the computer I don't know which my OBD2 monitors.


I've also checked the coolant level and performed the air bleeding procedure.


I don't think my OBD2 reader monitors any transmission data. There are no codes showing in the OBD2.

Any ideas or info appreciated.....Jim

[jclausen]

When the electric water pump starts to fail the electric fan comes on at very high speeds, quite loud. But there should be faults for that in the dme. The engine temperature is hot regardless of out side temp unless the temp is super low outside. Or the electric fan has something wrong with it. But you would think there would be faults for it also.

[mexjim]

Thanks for your reply. I too would expect faults codes or a warning light.

I'm wondering if my OBD2 reader, which shows no codes, is perhaps not able to retrieve codes on my BMW. Does someone have an easy way to force an error code that I could check with my OBD2 reader to confirm it's actually able to do that function?

Thanks...Jim

[jclausen]

Have a shop do quick read