# 2008 BMW 335xi Issue

**URL:** <https://community.cartalk.com/t/2008-bmw-335xi-issue/147747>\
**Category:** Maintenance/Repairs\
**Created:** [August 29, 2019, 5:04pm UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747 "2019-08-29T17:04:50Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Jpwns23](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jpwns23](https://community.cartalk.com/u/Jpwns23)\
**Post date:** [August 29, 2019, 5:04pm UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/1 "2019-08-29T17:04:50Z")

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I have a 2008 BMW 335xi with about 60k miles on it. Yesterday, out of nowhere all the electronics stared going crazy. The radio turned off, the windshield wipers started going for no reason. Then I got a whole bunch of errors: Trans. malfunction, awd, dsc, abs, and ebv. Then the car started overheating to the point that I had to shut the car off. Any thought on what could be wrong?

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**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\
**Post date:** [August 29, 2019, 5:15pm UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/2 "2019-08-29T17:15:09Z")

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This is just a wild guess from afar, but the first thing that I would check is to see if the serpentine belt is still intact. It is very possible that it broke, and both the alternator and the water pump stopped turning as a result.

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**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\
**Post date:** [August 30, 2019, 9:15pm UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/3 "2019-08-30T21:15:15Z")

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What did your mechanic find?

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**Author:** ![Jpwns23](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jpwns23](https://community.cartalk.com/u/Jpwns23)\
**Post date:** [August 30, 2019, 9:26pm UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/4 "2019-08-30T21:26:08Z")

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Taking it to the mechanic tomorrow. I will let you know

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**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\
**Post date:** [August 31, 2019, 2:47am UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/5 "2019-08-31T02:47:49Z")

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Is the battery dead? Will the engine start? That engine has an electric water pump, a low voltage condition will affect the cooling system.

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**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\
**Post date:** [August 31, 2019, 9:30am UTC](https://community.cartalk.com/t/2008-bmw-335xi-issue/147747/6 "2019-08-31T09:30:02Z")

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Those are signs of the alternator diodes failing and AC pulses are getting into the DC bus. Disconnect the alternator output wire and tape the wire connector so it can’t touch anything. That wire is hot to the battery. You are going to have to replace the alternator.