Removing the light switch unit

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albanoodle
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Removing the light switch unit

Post by albanoodle » Sat Oct 06, 2007 11:33 am

As preparation for a few other projects I needed to remove the light switch unit, this is how things went:

First of all you need to remove the small trim panel. I used a few plastic cards in lack of a better tool:

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I had to apply some force which felt uncomfortable, but off it came - and without too many scratches. Frontside:

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Backside:

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Note where the pins are located. This is a good indicator of where to apply pressure/leverage:

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After removing the trim panel, it's a simple two-screw job:

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The plug on top comes of easy using the lever mechanism on the plug. Here's the box:

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AN.

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srhutch
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Re: Removing the light switch unit

Post by srhutch » Sat Oct 06, 2007 5:05 pm

what the hells in that switch? it's enormous.
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GP20
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Re: Removing the light switch unit

Post by GP20 » Mon Oct 08, 2007 12:49 am

srhutch wrote:what the hells in that switch? it's enormous.
It's more than just a light control unit. :D It's one of the 2 places that keeps all the car's infomration including the car's mileage. Every time you turn on the ignition the car runs a test to make sure all the electrical parts are working properly and it's the light control unti's job. That's why sometimes if you change the light control unit without proper programming, or if you change out certain electrical parts on the car (for example, xenon headlight retrofit), the "mileage tempering light" shows up on the strument cluster because it thinks someone's trying to switch out the control unit from a different car and fraudfully tempering with the car's mileage.
'08 BMW Z4///MC 18" & 19" BBS RGR's|Michelin PSS'|TCK DA's 450/500|OEM CF spoiler|Aero side-skirts|ZHP gear-knob|OEM STB|
'06 BMW Z4///MR (sold)
'04 BMW Z4 3.0i 6sp SMG (lemon)
'03 BMW Z4 2.5i non-sport (sold)

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MarkC
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Re: Removing the light switch unit

Post by MarkC » Thu Oct 11, 2007 7:52 pm

GP20 wrote:
srhutch wrote:what the hells in that switch? it's enormous.
It's more than just a light control unit. :D It's one of the 2 places that keeps all the car's infomration including the car's mileage. Every time you turn on the ignition the car runs a test to make sure all the electrical parts are working properly and it's the light control unti's job. That's why sometimes if you change the light control unit without proper programming, or if you change out certain electrical parts on the car (for example, xenon headlight retrofit), the "mileage tempering light" shows up on the strument cluster because it thinks someone's trying to switch out the control unit from a different car and fraudfully tempering with the car's mileage.
Good to know. I was going to install the euro switch for the separate rear foglight and the night parking light option (will need to drill out the headlights to install the mini bulbs, as well as ID the wires for them as well as the rear foglight), now I'll have to figure something else out.

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Removing the light switch unit

Post by Silverfox03 » Fri Jan 19, 2018 8:58 pm

I have 2003 Z4 roadster w/o fog lamps. I am going to install fog lamps (confirmed the wiring / connectors already there ..), new relay and replace existing the "non-fog light light switch unit" with one with the fog light button. Will I require any "programming" to be done? If so, any insight as to what I will need to advise my "garage," all of whom are certified BMW mechanics.
Thanks

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srhutch
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Removing the light switch unit

Post by srhutch » Fri Jan 19, 2018 9:12 pm

Yes as the LCM holds mileage and you will get the mileage tamper dot up at the very least.
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Silverfox03
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Removing the light switch unit

Post by Silverfox03 » Fri Jan 19, 2018 10:21 pm

Appreciate the quick reply and instructions for LCM programming.

Frank_albert
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Removing the light switch unit

Post by Frank_albert » Wed Aug 15, 2018 3:52 pm

Bought a switch, second hand, with the fog light and automatic headlight activation. Realized after installing it that it needed programming. I have the PA software and the hardware, but how do I reprogram the LCM so that it works and I can clear the error codes.

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Removing the light switch unit

Post by juice619 » Thu Nov 28, 2019 1:54 am

Hello, was this issue ever solved? I am dealing with the exact same issue.

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srhutch
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Removing the light switch unit

Post by srhutch » Thu Nov 28, 2019 7:43 am

juice619 wrote: Thu Nov 28, 2019 1:54 am Hello, was this issue ever solved? I am dealing with the exact same issue.
What errors/issues do you have?
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