Blower Motor broken after Fuse taps for Dashcam

[mr_metropolitan]

‘02 M3, 80k mi - I got a weird one, hope y’all can help. I recently installed a Garmin Dashcam into the fuse box using a couple fuse taps into slots 23 (ACC) and slot 66 (Batt). These slots were unoccupied at the time of install.

Ever since the blower motor has been inoperable on the car. What I’m trying to figure out is if I did something to cause an issue or it’s a coincidence that the blower or FSR went at the same time. Thanks for any help.

[sapote]

Why do you need to have 2 power sources -- 2 fuse slots -- for the camera? Did you check the 2 fuses that are related to the heating/cooling system?

[mr_metropolitan]

Oh I should have mentioned. I installed a Garmin parking mode cable (https://www.garmin.com/en-US/p/587564). It has two power connections, BATT for constant power even when the key is off and ACC for when the key is in the first position (accessory position). This combination allows for the parking mode to be enabled.

I chose 23 for ACC since it had keyed on power and was open and 66 for the BATT since it had constant power when keyed off it was open, and it is used for the SMG (my car is a manual).
I checked all the fuses relating to blower, AC, and heater. They are all good.

[sapote]

I checked all the fuses relating to blower, AC, and heater. They are all good.

F50 and F28 have 12v with key turned on?

[simonnim]

I would remove the blower motor and inspect. I don't know if it's a freak accident but my blower motor on my z3m melted one of the terminals. Had to cut the wire behind the burnt terminal and press a new one on. Not sure the reason but maybe it was some fault in the final resistor? I replaced that first.

[Pnick]

‘02 M3, 80k mi - I got a weird one, hope y’all can help. I recently installed a Garmin Dashcam into the fuse box using a couple fuse taps into slots 23 (ACC) and slot 66 (Batt). These slots were unoccupied at the time of install.

Ever since the blower motor has been inoperable on the car. What I’m trying to figure out is if I did something to cause an issue or it’s a coincidence that the blower or FSR went at the same time. Thanks for any help.

Might be a coincidence but I would disconnect the dashcam first and see if it starts to work. If it doesn't, then a deeper dive into the root cause should be your next step. Simple quick steps first before you start taking things apart.

[mr_metropolitan]

F50 and F28 have 12v with key turned on?

yup they both have power keyed on.

Might be a coincidence but I would disconnect the dashcam first and see if it starts to work. If it doesn't, then a deeper dive into the root cause should be your next step. Simple quick steps first before you start taking things apart.

I should have mentioned this was the first step I tried, but it was no luck.


I came back to the car after traveling for a few days and on first start-up the blower motor hesitated, but roared to life after a few seconds. I'm guessing either that or the resistor is on its way out.

[sapote]

Replace the FSR

[mr_metropolitan]

Just to close this one out, I replaced the FSR and blower works 100% and heater blows hotter/ac blows colder.