# 2007 BMW X3 e83 rear light mystery \*solved\*

**URL:** <https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322>\
**Category:** Maintenance/Repairs\
**Created:** [September 30, 2015, 9:40am UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322 "2015-09-30T09:40:43Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![ContraAl](https://avatars.discourse-cdn.com/v4/letter/c/4da419/32.png) [@ContraAl](https://community.cartalk.com/u/ContraAl)\
**Post date:** [September 30, 2015, 9:40am UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/1 "2015-09-30T09:40:43Z")

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Here’s one for the Bimmer guru’s. This one is really eluding me. I couldn’t find it in the owner’s manual and my online WDS manual got taken down. Both connectors for the bulb are resting at ground when the lights are on.

The question is… What condition activates this light? (see pic)

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**Author:** ![Manolito](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/manolito/32/3070_2.png) [@Manolito](https://community.cartalk.com/u/Manolito)\
**Post date:** [September 30, 2015, 5:21pm UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/2 "2015-09-30T17:21:57Z")

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In your regular owner’s manual, it should mention that on this car, your brake lights get brighter if you press the brake pedal extra hard. My guess is that this light is what makes the brighter brake light.

A second, less likely possibility, would be a fog light. My old Volvos lit an extra bulb in the rear whenever the fog lights were on.

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**Author:** ![lion9car](https://avatars.discourse-cdn.com/v4/letter/l/59ef9b/32.png) [@lion9car](https://community.cartalk.com/u/lion9car)\
**Post date:** [September 30, 2015, 5:34pm UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/3 "2015-09-30T17:34:17Z")

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This is your “brake force display” lamp. See the section “Brake force display” in your owner’s manual on page 55. They should have included this in the diagram on page 107, where you were probably looking, but for some reason they didn’t.

If you think it’s burned out or you want to double-check this, I guess you’ll need a friend and an empty stretch of road.

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**Author:** ![ContraAl](https://avatars.discourse-cdn.com/v4/letter/c/4da419/32.png) [@ContraAl](https://community.cartalk.com/u/ContraAl)\
**Post date:** [September 30, 2015, 10:00pm UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/4 "2015-09-30T22:00:50Z")

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Thanks! I’ve been trying to troubleshoot a bulb out indicator light and those were the only ones that didn’t come on. The bulbs are still good and light up when I put them on the battery.

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**Author:** ![knfenimore](https://avatars.discourse-cdn.com/v4/letter/k/9fc348/32.png) [@knfenimore](https://community.cartalk.com/u/knfenimore)\
**Post date:** [October 1, 2015, 5:44pm UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/5 "2015-10-01T17:44:43Z")

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They are hard braking indicators.  
[http://x3.xbimmers.com/forums/showthread.php?t=623084](http://x3.xbimmers.com/forums/showthread.php?t=623084)

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**Author:** ![ContraAl](https://avatars.discourse-cdn.com/v4/letter/c/4da419/32.png) [@ContraAl](https://community.cartalk.com/u/ContraAl)\
**Post date:** [October 2, 2015, 11:42am UTC](https://community.cartalk.com/t/2007-bmw-x3-e83-rear-light-mystery-solved/91322/6 "2015-10-02T11:42:21Z")

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Ah, cool thread @knfenimore . I don’t think I would have found that F25 thread because mine is a E83.