How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Kevin Your Own Question
Kevin, BMW Mechanic
Category: BMW
Satisfied Customers: 1972
Experience:  Diagnostic technician
Type Your BMW Question Here...
Kevin is online now
A new question is answered every 9 seconds

My name is ***** *****. I recently purchased a 2004 745i. It

Customer Question

Customer: Hi. My name is ***** *****. I recently purchased a 2004 745i. It drove and handled like brand new when i first got it. But now after its been running for a few minutes it does weird things. First it will have a message on cluster saying dynamic stability issue. then trans fail safe mode. then the whole dash will go blank. the one thing i have noticed is when it does this weird stuff the charging system will be over charging the batt. like at 18 - 20 v.
JA: Thanks. Can you give me any more details about your issue?
Customer: yes the Batt is brand new. and at times the trunk smells like acid. If i leave the climate control system and the entertainment system turned off it takes longer to act up
JA: OK got it. Last thing – JustAnswer charges a fee (generally around $18) to post your type of question to BMW Experts (you only pay if satisfied). There are a couple customers ahead of you. We can help you for less if you're not in a rush. Are you willing to wait a bit?
Customer: sure thing
JA: OK. Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.
Category: BMW
Expert:  Kevin replied 1 year ago.

Hi I'm Kevin sorry to hear of your troubles where and how are you checking the charging voltage?

Customer: replied 1 year ago.
Hi Kevin. Well ive checked the voltage multiple ways. at the batt. at the jumpstart post under the hood, and also at the back of the Alt. charging voltage after start uo is approx 13.6. but when the dynamic stability light comes on or the trans. failsafe message comes on the voltage is always like 18 or higher.
Customer: replied 1 year ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Expert:  Kevin replied 1 year ago.

Hi sorry for the delay this indicates that the voltage regulator on the alternator is failing and at times overcharging .i would not recommend running vehicle until a new alternator is fitted as overcharging can cause irreversible damage to computer systems