Audi - Halogen to LED tail light retrofit

Halogen to LED tail light retrofit

Status:

This retrofit has been succesfully implemented and tested on mine A4 B9, and it’s still active.

100%

Needed parts:

LED tail lights units
Adapter cables (Aliexpress)
Covers for internal and external lights
- 8W5 945 253
- 8W5 945 254
- 8W5 945 255
- 8W5 945 256
VCP diagnostic interface

Price:

Parts listed above

600 €

I bought on Ebay from a private user this awesome set of LED tail lights for my A4 B9 Sedan (Part no. 8W5 945 094 etc.)

You also need a wiring cable set (bought from Aliexpress)

Link: https://it.aliexpress.com/item/4000462948570.html

Step 1 – Remove rear bumper and trunk cover

You must remove the rear bumper in order to insert the extra wire for the dynamic turn signal.

The trunk cover must be removed too for the internal lights wires.

Step 2 – BCM2 and LEDs wiring

Note: check your BCM2 part no. and pinout, check for the presence of the male PIN T17b/11.

If that pin isn’t present on your BCM2, you must connect all the wire in parallel to 12v in the fuse box (1A fuse)

Note2: You need to remove a small piece of plastic from the original MX5 and MX6 connector in order to fit the female socket on the internal lights LED unit.

Electrician scissors should do the job.

MX5 [Int SX] Move pin T6ab/3 to T6ab/5

Add the following 3 pins:

BLACK to T6ab/6 to hook up at 12v (or T17b/11 if present)
WHITE GREY to T6ab/3 to hook up to BCM2 T17a/14
BLUE VIOLET to T6ab/4 to hook up to BCM2 T17b/3 ALREADY OCCUPIED on BCM2, it must be removed.

MX6 [Int DX] Move pin T6ac/3 to T6ac/5

Add the following 3 pins:

BLACK to T6ac/6 to hook up at 12v (or T17b/11 if present)
GREEN to T6ac/3 to hook up to BCM2 T17b/5
WHITE BLACK su T6ac/4 to hook up to BCM2 T17a/1 ALREADY OCCUPIED on BCM2, it must be removed.

MX3 [Ext SX] Plug and play, just take the black wire and hook it up at 12v (or T17b/11 if present)

MX4 [Ext DX] Plug and play, just take the black wire and hook it up at 12v (or T17b/11 if present)