Stuck!! X5 3.0i starting issue - Intermittant Cranks well but doesn't start in AM

[Ratman2356]

Hi folks, 03 X5 3.0i auto 100k miles. Was running fine until yesterday. Would not start although it cranked strongly during starting attempts. I came inside to look up some info and went back out an hour or so later to try to check some onboard diag info. Tried to start it first and it half caught on the first try and then started the 2nd try. I drove it to autozone and they checked it for codes. None found. Checked battery, 41% but tested ok. Drove it around a bit and then home. Started up fine a few more times through the day. Put the charger on it through the night to make sure battery was full from all the cranking I did on it.

This morning same thing as yesterday. Will not start but cranks strong. Info: Installed new battery and alternator 3 months ago. Just got it back from shop last week after having CV axles, A/C system and thermostat replaced.

I noticed that the battery light stays lit while trying to start it. I have never noticed this in the past but it always started right up so not sure I would have. Can anyone tell me if it is supposed to light up while cranking? I am wondering if it is indicating a failed alternator again although it did not light up at all yesterday while driving.

Any other things to check that maybe the mechanic might have knocked loose or not tightened correctly during those procedures that could cause this?

I thought maybe Crankshaft sensor but if I understand correctly, that is an all or nothing thing and it would not have started at all yesterday. Fuel pump going out is another possibility which is why I am trying to eliminate the alternator first as that batt light is only thing I have to go on right now. Can someone check their X5 and see whether it stays lit while cranking the engine over please?

Pulling my hair out here. Thanks!

Rob