Where is power feed for rear window heater?

nemesis_318 · 10-19-2010, 07:14 AM

Where does the power feed into the rear window heater grid?

Someone told me it was behind the passenger C-pillar from that little black box. But I looked up that part and it's a trap circuit for the FM antenna.

I am trying to troubleshoot a non-functioning rear window heater.

Also, I can't seem to find the rear window heater or anything to do with it on realoem.com, what is it listed under?

paraklas · 10-19-2010, 08:00 AM

This black box? Are you getting 12v to the grid? It's controlled by the HVAC unit

Maybe it's from the other side:

nemesis_318 · 10-19-2010, 08:32 AM

Yes, the black box in the first picture is the one I am referring to.

realeom.com and the local BMW dealer identifies this as part number 65 24 8 380 944 Trap Circuit for FM Antenna. Is this incorrect? To me that looks like the connection for the grid but why is it identified as a trap circuit for the fm antenna.

Your second picture from the divers side, the realoem.com guide identifies that box as the amplifier, i am assuming the amplifier for the antenna??

I checked those two leads going from the box (in the first pic - passenger side) to the grid and I do not get 12 volts there, or any voltage for that matter.

The relay for the rear window heater located in the trunk 'clicks' when the heater button is pushed, the rear window heater light comes on, and the fuse is good, but no heat to the grid.

10-19-2010, 07:14 AM	#1
nemesis_318 Registered User Join Date: Sep 2009 Location: Michigan Posts: 14 My Ride: 1999 323i View My Garage	Where is power feed for rear window heater? Where does the power feed into the rear window heater grid? Someone told me it was behind the passenger C-pillar from that little black box. But I looked up that part and it's a trap circuit for the FM antenna. I am trying to troubleshoot a non-functioning rear window heater. Also, I can't seem to find the rear window heater or anything to do with it on realoem.com, what is it listed under? Last edited by nemesis_318; 10-19-2010 at 07:19 AM.

10-19-2010, 08:00 AM	#2
paraklas OEM ///Member Join Date: Jan 2006 Location: Cyprus Posts: 5,401 My Ride: ESS TS2 320ci View My Garage	This black box? Are you getting 12v to the grid? It's controlled by the HVAC unit Maybe it's from the other side: __________________ Last edited by paraklas; 10-19-2010 at 08:03 AM.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes	Rate This Thread
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode	Rate This Thread:

10-19-2010, 08:32 AM	#3
nemesis_318 Registered User Join Date: Sep 2009 Location: Michigan Posts: 14 My Ride: 1999 323i View My Garage	Yes, the black box in the first picture is the one I am referring to. realeom.com and the local BMW dealer identifies this as part number 65 24 8 380 944 Trap Circuit for FM Antenna. Is this incorrect? To me that looks like the connection for the grid but why is it identified as a trap circuit for the fm antenna. Your second picture from the divers side, the realoem.com guide identifies that box as the amplifier, i am assuming the amplifier for the antenna?? I checked those two leads going from the box (in the first pic - passenger side) to the grid and I do not get 12 volts there, or any voltage for that matter. The relay for the rear window heater located in the trunk 'clicks' when the heater button is pushed, the rear window heater light comes on, and the fuse is good, but no heat to the grid.