# BMW 2005 535d electrical power and computer problems

**URL:** <https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432>\
**Category:** Maintenance/Repairs\
**Tags:** computers, transmissions, electrical-wiring\
**Created:** [June 14, 2014, 5:28pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432 "2014-06-14T17:28:40Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Slancio](https://avatars.discourse-cdn.com/v4/letter/s/6f9a4e/32.png) [@Slancio](https://community.cartalk.com/u/Slancio)\
**Post date:** [June 14, 2014, 5:28pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432/1 "2014-06-14T17:28:40Z")

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My BMW 535d seems to be having power issues. While driving the computer fails… I loose all systems… Auto trans, steering, brakes, tire monitor, GPS etc. Sometimes all the indicator lights flash. I need to pull over and restart the car so computer reboots. Until it happens again. Can’t drive fast with transmission in this condition. I notice if I accelerate fast it seems to provoke the reaction. Before this began to happen, the date and time had to be reset after parking the car overnight a few times. I also notice the battery warning light when pulling over to reboot computer. I had it to the dealer now twice. First time they failed to fix it. They just serviced the car. When pulling out of parking lot of dealer it happened again. I brought it right back. Then they replaced a relay switch that they said was hot. That did not do it. I bought it back again. They’ve now had the car four days. This is BMW Dijon, France. Can it be this is a bad dealership? I find it strange that they can not find the problem… esp now that it is easy to cause it to happen. Any ideas?

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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:** [June 14, 2014, 5:37pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432/2 "2014-06-14T17:37:31Z")

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My best guess would be a failing alternator.  
When electronic devices are not given a consistent flow of electrical energy, they will produce all manner of…strange…reactions.

Have the alternator output checked.

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**Author:** ![Slancio](https://avatars.discourse-cdn.com/v4/letter/s/6f9a4e/32.png) [@Slancio](https://community.cartalk.com/u/Slancio)\
**Post date:** [June 14, 2014, 5:44pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432/3 "2014-06-14T17:44:30Z")

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Is there some sort of voltage control on this car as well? And thanks for the advice

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**Author:** ![Slancio](https://avatars.discourse-cdn.com/v4/letter/s/6f9a4e/32.png) [@Slancio](https://community.cartalk.com/u/Slancio)\
**Post date:** [June 14, 2014, 5:52pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432/4 "2014-06-14T17:52:54Z")

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I seem to have read somewhere there was a ground issue with some of these BMW’s too… do you know anything about that? And thanks again

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**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\
**Post date:** [June 14, 2014, 7:26pm UTC](https://community.cartalk.com/t/bmw-2005-535d-electrical-power-and-computer-problems/85432/5 "2014-06-14T19:26:08Z")

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You’ve probably seen this, and yes, ground problems can wreak havoc on any car:

[http://www.bimmerfest.com/forums/showthread.php?t=304000](http://www.bimmerfest.com/forums/showthread.php?t=304000)