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CirrusSR22 · 06-08-2008, 04:48 AM

I had two scrap pieces of 12 AWG so they were splice together under the rear seat. You can see how the battery supply wire can now rejoin the factory bundle. I’m guessing if you were to remove the front seat you could follow the factory bundle right from the firewall.

Finally the battery supply wire (now orange!)can follow the factory bundle to where we will mount the converter.

#6. Reconnect the negative battery cable.

#7. Time for some actual work! We need to splice the converter’s wiring into the car’s wiring. It uses these signals for logic, and powers the actual trailer lights through the battery wire we just ran to the unit. I initially tried to solder my wires and use heat shrink tubing but my soldering gun was too weak. The converter kits usually come with “taps”, but they seem quite cheesy. I chose to cut my car wires and use crimp style butt splices to complete the connections. I made the connections at the bundle that slopes downward from the wheel well.

Please don’t take my word on these wire colors!!!! Take out your handy Bentley manual and use your multimeter to make certain your are splicing into the proper wires.

(CONVERTER WIRE : BMW Wire Color)
BRAKE WIRE : BLUE w/ RED STRIPE
LEFT TURN : BLUE w/ GREEN STRIPE
RIGHT TURN: BLUE w/ BROWN STRIPE
TAIL LIGHT: GREY w/ YELLOW STRIPE. This wire leads to the right tail light. You should also be able to use the GREY w/ VIOLET wire which leads to the left tail light

Here’s where we will splice into the factory bundle.

Here’s the bundle after the splices are complete. Re-wrap your bundle with electrical tape when you are done.

#8. After all wiring is complete, install the supplied fuse in the inline fuse holder and test your lights. My U-Haul converter came with handy LED’s built into the connector end to see what’s going on. If not, plug the converter into you trailer and check their operation. Hopefully all is well!!!

#9. Now comes time to mount the converter in the trunk. I made a metal holder that bolts into the lower two nuts of the CD changer location. If you actually have a CD changer, you’ll have to get creative. If worst comes to worst, use the double sided tape on the back side of the converter and stick it somewhere. Here's the mount I made.

And the converter stuck to it.

#10. Finally you’ll need to find a way to route the four-flat wire outside of the car. I haven’t really explored this yet, and I assume you could just close the hatch on the wire and it would be fine on a temporary basis.

Enjoy! Remember..... Buy trailers, not trucks!!

06-08-2008, 04:48 AM	#2
CirrusSR22 Senior Member Join Date: Nov 2004 Location: Minneapolis Posts: 1,587 iTrader: (3) Photo Gallery	I had two scrap pieces of 12 AWG so they were splice together under the rear seat. You can see how the battery supply wire can now rejoin the factory bundle. I’m guessing if you were to remove the front seat you could follow the factory bundle right from the firewall. Finally the battery supply wire (now orange!)can follow the factory bundle to where we will mount the converter. #6. Reconnect the negative battery cable. #7. Time for some actual work! We need to splice the converter’s wiring into the car’s wiring. It uses these signals for logic, and powers the actual trailer lights through the battery wire we just ran to the unit. I initially tried to solder my wires and use heat shrink tubing but my soldering gun was too weak. The converter kits usually come with “taps”, but they seem quite cheesy. I chose to cut my car wires and use crimp style butt splices to complete the connections. I made the connections at the bundle that slopes downward from the wheel well. Please don’t take my word on these wire colors!!!! Take out your handy Bentley manual and use your multimeter to make certain your are splicing into the proper wires. (CONVERTER WIRE : BMW Wire Color) BRAKE WIRE : BLUE w/ RED STRIPE LEFT TURN : BLUE w/ GREEN STRIPE RIGHT TURN: BLUE w/ BROWN STRIPE TAIL LIGHT: GREY w/ YELLOW STRIPE. This wire leads to the right tail light. You should also be able to use the GREY w/ VIOLET wire which leads to the left tail light Here’s where we will splice into the factory bundle. Here’s the bundle after the splices are complete. Re-wrap your bundle with electrical tape when you are done. #8. After all wiring is complete, install the supplied fuse in the inline fuse holder and test your lights. My U-Haul converter came with handy LED’s built into the connector end to see what’s going on. If not, plug the converter into you trailer and check their operation. Hopefully all is well!!! #9. Now comes time to mount the converter in the trunk. I made a metal holder that bolts into the lower two nuts of the CD changer location. If you actually have a CD changer, you’ll have to get creative. If worst comes to worst, use the double sided tape on the back side of the converter and stick it somewhere. Here's the mount I made. And the converter stuck to it. #10. Finally you’ll need to find a way to route the four-flat wire outside of the car. I haven’t really explored this yet, and I assume you could just close the hatch on the wire and it would be fine on a temporary basis. Enjoy! Remember..... Buy trailers, not trucks!!