E92 N54 no start no crank?

Eurofam

Private
Oct 4, 2020
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Hey guys so my 335i is giving me an intermittent no start issue, put the key in push button all lights come on fuel pump primes but doesn’t even try to crank as if the starter isn’t getting power. Battery is brand new, starter is 4 months old.

I tried jump starting it from under the hood to see if that made a difference and it didn’t so I took the ground cable from the jump box and put it on the alternator bracket and she fired right up.

my questions are since it started after moving the ground to the block would that mean my alternator is on it’s way out or would that point to a bad ground? Maybe ground straps to chassis? It doesn’t do this often maybe every 10-15 starts

I should also add during the times I tried starting it without the jump box and it would not crank I kept getting the bsd data bus communication fault and occasionally bsd Alternator missing/coolant pump missing. No it does not overheat when running and no there are no voltage drops/drains/charging issues.
 

NoGuru

Captain
Jan 9, 2018
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Just North of Detroit
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Humm, this is hard to say but I would think the ground strap would be the issue. You can replace the brushes on the alternator for pretty cheap. Might want to do that anyway.
 

Eurofam

Private
Oct 4, 2020
42
7
0
I replaced the ground strap with a much thicker gauge cable and so far so good, even starts quicker than before
 
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