Hardwire dashcam or radar detector using homelink wires

doublespaces

General of the Army
Oct 18, 2016
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AZ
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2009 E93 335i
I have a dashcam and I have to take it out each time I work on the electronics of my car so I'd like to hardwire it without running a wire down the A pillar airbag. I have seen a DIY on how to do this using the homelink power(included below), but it was for an E90 I believe, my E93 looks a bit different. I suspect there will be some sort of power up there regardless so I'm hoping this may still work.

My question, has anyone done a hardwire job like this without running a power wire down the side of the car? And if I got a radar detector later, I wonder if I'd be overloading that wire running the homelink, radar detector and dash cam simultaneously. I suppose I'd need to check and see what the fuses is rated for also.

Here is the guide I found previously:

01 - Opening Panel 01.JPG
02 - Opening Panel 02.JPG
03 - Ground Contact.JPG
04 - Wiring 01.JPG
05 - Wiring 02.JPG
06 - Splice 01.JPG
07 - Stowing Away.JPG
 

LessIsMore

Specialist
Aug 21, 2017
56
22
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Ride
09 535i
subbed, Would like to know if this works well.
I have a dashcam I haven't installed due to laziness and other priorities. Also don't want wires down the pillar.
I have a 535i, assuming I'm going to find things a little different up there, but these pics should help somewhat.
 

doublespaces

General of the Army
Oct 18, 2016
8,945
4,152
0
AZ
Ride
2009 E93 335i
subbed, Would like to know if this works well.
I have a dashcam I haven't installed due to laziness and other priorities. Also don't want wires down the pillar.
I have a 535i, assuming I'm going to find things a little different up there, but these pics should help somewhat.

Do you also have the homelink stuff? If so, there is some power up there. I'm mainly curious how much of a load is safe to put on that wire, hopefully enough to run homelink and two devices.
 

LessIsMore

Specialist
Aug 21, 2017
56
22
0
Ride
09 535i
Yep, have homelink, and know power is up there somewhere, but haven't taken a look and not sure if can expect it to be same wires/colors/etc.
I think you had it right with - check the fuse rating, try it out with all 3 and if it blows, you know you have to remove one of the components from that circuit. Otherwise you'd have to measure draw on each device, add them up, etc. - and it may vary at different modes/operations for each, so rough-and-quick way is just try it and see if fuse blows. :)
 

dyezak

Major
May 4, 2017
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Plano TX
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335is
The answer to your question is found here https://www.powerstream.com/Wire_Size.htm

Power handling capability is determined by the media conducting that power, in this instance it's the wire gauge. Just get a pair of calipers and measure the wire (once found, and measure a stripped section so you don't include the plastic...only measure the wire itself) and look up what gauge it is. Then reference the linked chart above and you know exactly how much power that wire would be capable of handling.

EE101
 
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VACust

Corporal
Dec 1, 2016
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US - Utah
I have HomeLink in my E92 and E90 335d. I hardwired both cars for my Escort RedLine using the above posted method and both cars were identical. When I did the first install in the E92 I did find there are other wires that had power only with ignition on and constant power in the far left connection (driver side) and what I believe/remember was the SOS switch. I used ignition on power for the radar detector hard wire and planned to dig into constant power for a future dash cam install. I want constant power for a motion activated camera. I thought it would be worth looking into at least.
 
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