'04 tail lights on '02

[AdamE53]

Hey there, just a quick question regarding tail lights.
I have an 02 X5 with the amber tail lights. They were corroded so I found some post face lift tail lights and swapped them in. They work perfectly fine but now my dash says that both tail lights are out. Any ideas why my dash is saying they don't work?

[Henn28]

Electrics aren’t my strongest suit, but I’m going to guess it is related to differences in the pulse width modulation coding between the OE and new lights.

[wpoll]

Simpler than that - the tails are not plug and play between pre-LCI and LCi. The wiring is different and the bulbs are different.

[TriX5]

I think the switch was not at pre/post-face lift. My '03 is pre-face lift but I am using post facelift tail lights without a mod. I think the wiring assignments in the taillight connector are different for some earlier years.

[wpoll]

There are pin assignment differences, along with bulb differences and differences in the circuit tracks in the tail assembly.

The pre-LCI uses a dual filament 5W/21W tail/brake bulb while the LCI uses a single filament 21W bulb that is PWM modulated from dim (tail) to bright (brake).

This change may have occured prior to the LCI change date (09 2003?) as BMW modified the assembly line for LCI builds. The change in tail lights would also infer a change on the LCM etc...

[AdamE53]

Thanks for all the replies everyone. I'm wondering if I can merge the two assemblies together: older connector/board with newer lenses. The newer lenses are in immaculate shape and I like the clear turn signals more than the amber ones.

[wpoll]

Originally Posted by AdamE53

Thanks for all the replies everyone. I'm wondering if I can merge the two assemblies together: older connector/board with newer lenses. The newer lenses are in immaculate shape and I like the clear turn signals more than the amber ones.

Should be possible - you'll have to drill out the plastic "rivets" and use JBWeld or similar to hold the assembly together.

[AdamE53]

That's what I figured. Doesn't seem too difficult to swap.
I'll update when I do it successfully.
Also, on a side note. When do the upper brake lights activate in the rear tail light?

[wpoll]

Originally Posted by AdamE53

Also, on a side note. When do the upper brake lights activate in the rear tail light?

On the LCI cars, all four rear red lights act as tail lights, with the lower reds doubling as brake lights.

The upper reds only light up as brake lights under high-force braking (i.e. when ABS kicks in!): -



I have heard of folk wiring the pre-LCI car rear lights to add the upper red lamps as brake lamps. Just a single jumper wire on each side, I think.

[andrewwynn]

I'm "that folk".

I had an '01 but had replaced tail lights due to an accident. I noticed that the 21w filament had a trace that went nowhere. I added a jumper so all four brake lamps lit when braking.

Also, there exists a jumper than will adapt before and after LCI hookups.