This car has "flick start" meaning the starter will keep on running till the engine fires, you physically do not have to hold the key to start. Just twist and leave it.

The starter will let go after 10 seconds of cranking and no rpm signal above 300.

If the starter is stopping midway, you need to hot wire the starter and test it for health. Remove the box cover and you will see the K40 relay, The center connector has a thick purple/white wire. Remove this connector and wire up a jumper from the positive jump start post. Apply 12V positive to this wire with it removed from the K40, the engine should start to crank even with key not in the switch. (make sure car is in P)

if it cranks good and fast. the starter is good.

Next up - check the display and verify that you see the gear indicator in the gauges. does it change as you shift from P to D?

if you see it disappear for a few moments, you have issues in the gear selector and it can cause this no start - and can also cause the transmission to "neutral" or go into hard limp mode.

If the trans passes, I would suggest you check the connector, wiring and also the CPS - the ECU looks for the rpm signal when cranking. if it sees a corrupt signal it will stop the cranking. (just like later chevy)

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)