[Sanji_4747]

Hello I’m a new user here I’m having trouble with my car not wanting to start it’ll start with a jumpstart but not on its own and when I turn it off it doesn’t start back up unless I jump it again I replaced the battery around late December and I’m about to replace the IBS not sure if that’ll help or not but if anyone has any ideas on what it could be I’d be interested in hearing what you have to say.

[Mack261]

Iam trying remember i had hard start yrs ago...Iam pretty sure i Unplug ibs sensor. Easy way is just unconnect blue wire above neg terminal. Is the airbag warning light on? Do you have power to lights inside car, windows work? After you jump car and pull jumper off does car stall.. If you read codes on car? are you getting code says postive battery interrupted?IF you have that codes no power is getting to starter and the engine fuse box. If so you might check the postive battery cable. The bst might be blown. You might need new postive battery cable. Think fcp euro like 124 bucks.. Look up Jack Myers on utube. Title is Bmw wont start after collision.

[Sanji_4747]

But don’t you have to have the ibs plugged in ?

[eljay]

Check that the alternator is working fine. What voltage do you see at the terminals under the hood when the car is running?

[StradaRedlands]

Check alternator, wiring, IBS, ground... it's one of those! Take it to an Autozone or similar and they'll check it out.

[relative4]

Originally Posted by Sanji_4747

But don’t you have to have the ibs plugged in ?

Hell no, I had my wife's unplugged for 6 years because the rear defroster wouldn't work if it was plugged in.

[relative4]

1. Pull codes - with a real scanner such as BimmerGeeks ProTool, not the junk AutoZone uses

2. With the car running, check the voltage
a. across the under-hood terminals
b. across the battery terminals

3. With the car turned off, check the voltage across the battery terminals