BimmerFest BMW Forum banner

Battery drain after changed antenna module

605 Views 3 Replies 3 Participants Last post by  freestyle31225
My '02 e46 was imported from Japan and it had infamous infrared key which only works from couple meters. So i did retrofit of radio frequency key and changed antenna module as mine did not had radio frequency receiver for key. I followed instruction on the forums and connected 2 wires from new module to gm5 and fuse pins as mentioned and paired the key new to the car. The Key now locks/unlocks car fine and starts the engine with the transponder from the old key.
Also forgot to mention that i've removed climate controls while installing it just to feed wires to the fuse box from under the console. And disconnected the battery for couple hours.

SO NOW THE BATTERY DRAIN PROBLEM: Car starts normally after sitting for 2-3 day locked, but when unlocked 15-20 mins later it won't even try to spin a starter, just clicks and flashes headlights. I checked for errors with INPA there's only 1 error and its's power on reset
Also when i try to start the car the blower fan makes the noise like "drrrr" for 15-20 seconds.

Can it be FSR? And why does it do it after i did the module change? If it's FSR can i fix it w/o replacing?
Any help would be appreciated, thanks
1 - 4 of 4 Posts
The FSR is not repairable. If bad, it must be replaced.

Did you need to CODE the general module to accept the keyless entry from the RF? I don’t mean key sync, I mean coding.


Sent from my iPhone using Bimmerfest
I just changed my FSR a few days ago. It's not an expensive part but it's an awkward job to do. Not technically challenging but certainly ergonomically challenging.
it's not a keyless entry, it's just a regular key which works in radio frequency not infrared. So i did not code anything just swapped antenna module and connected 2 wires from it to the GM5's pin 49 and back of the fuse 49.
I'm just wondering if i could do something with the cable's which can cause battery drain. Cause it's not draining while the car is locked. When i unlocked the car and started it after 2 days sitting it started just fine. I let it warm for 5-8 mins then turn of engine and connected INPA to look at some data. 10 mins later it won't even trie to spin the starter.

Doesn't FSR drain the battery even if the car is in locked/sleep mode?
And why would blower make that weird noise when i did nothing to it?
Can it be a loose fuse or something? Cause i removed fuse box to access GM5
The FSR is not repairable. If bad, it must be replaced.

Did you need to CODE the general module to accept the keyless entry from the RF? I don***8217;t mean key sync, I mean coding.

Sent from my iPhone using Bimmerfest
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top