Blower motor only works for windshield in cold weather

Godzilx · 01-15-2024, 03:25 PM

Yesterday morning it was around -10°F out, I get in my car and turned on the heat. It would only blow air out the windshield defroster port, and when I tried switching it to blow air in the footwell/towards the driver, the fan would turn off.

Overnight I let my car sit in a heated garage and now it works again.

How can I fix this to prevent it from happening again? Blower motor seems to work perfectly but only on the windshield when cold, so the source of the problem is confusing.

Car is a 2007 E90 335i

Thank you!

Efthreeoh · 01-17-2024, 08:17 AM

I think it is just your battery is low on charge. Drive the car a few hours or put a battery tender on the under hood jump points to charge the battery. How old is the battery?

It is cold, which reduces the battery's ability to produce electricity. The car has logic built into the electrical system to limit high-energy demand devices such as the blower motor. It will run the blower on high only in case the windshield needs clearing as a safety precaution.

01-15-2024, 03:25 PM	#1
Godzilx Private 16 Rep 94 Posts Drives: 2007 335i Join Date: Sep 2019 Location: Illinois iTrader: (0)	Blower motor only works for windshield in cold weather Yesterday morning it was around -10°F out, I get in my car and turned on the heat. It would only blow air out the windshield defroster port, and when I tried switching it to blow air in the footwell/towards the driver, the fan would turn off. Overnight I let my car sit in a heated garage and now it works again. How can I fix this to prevent it from happening again? Blower motor seems to work perfectly but only on the windshield when cold, so the source of the problem is confusing. Car is a 2007 E90 335i Thank you!
	Appreciate 0 Tweet Quote

01-17-2024, 08:17 AM	#2
Efthreeoh General 19186 Rep 19,718 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	I think it is just your battery is low on charge. Drive the car a few hours or put a battery tender on the under hood jump points to charge the battery. How old is the battery? It is cold, which reduces the battery's ability to produce electricity. The car has logic built into the electrical system to limit high-energy demand devices such as the blower motor. It will run the blower on high only in case the windshield needs clearing as a safety precaution. __________________ A manual transmission can be set to "comfort", "sport", and "track" modes simply by the technique and speed at which you shift it; it doesn't need "modes", modes are for manumatics that try to behave like a real 3-pedal manual transmission. If you can money-shift it, it's a manual transmission. "Yeah, but NO ONE puts an automatic trans shift knob on a manual transmission." Last edited by Efthreeoh; 01-17-2024 at 05:00 PM..
	Appreciate 0 Quote