2008 BMW X5 3.0i motor won't start....was running nite before...turned car of before putting in park....would that cause a problem

You probably need to replace the crank position sensor. You might need to do a tune up of plugs and coil packs too. If you've been putting in cheap Chinese tune up parts you'll cause the sensor to go out...

read the code to see what caused the failsafe to engage.

I think it is most likely a wiring problem causing this. Titans are notorious for having the exhaust rust through after the muffler. I would trace the passenger side wiring harness back and check for fused together wires. I take it your Titan is a floor shifter not a column. If so I suggest taking the circular cap off right by the shifter (shift interlock over ride). If you can put a key in and compress the over ride then you should be able to shift through gears to rule out a transmission problem. No maf sensor would cause this, nor would a bad transmission. Make sure to check all fuses that are labeled electronic parts, they are connected to your interlock system. The abs and wheel speed sensor is what is making it impossible to shift into 4x4 . All of these problems are separate fuses, but the wires are all in the same harness running past the exhaust.

Could be a faulty motor or ground circuit.
You would need to check the power and ground circuit at the motor when it won't run.

It may be the solenoid (electro-magnetic clamp) that engages the starter motor with the flywheel to start the car. Unfortunately, this usually involves replacing the entire starter.

Hey Gordon,
Remove your battery, take it to O'Reilly's, AutoZone, etc.. have them check the CCA (Cold Cranking Amps)-load test.
.. this is what makes your car crank.>Amperage< ... 12+ volts might run the lights.. but just voltage WILL NOT crank your car.. the age of the battery doesn't matter either..

car is sensing a problem with the stability control system (DSC) or the antilock brake system (ABS). usually an ABS problem will turn off the DSC, so DSC may be ok, just ABS needs a look at.

since its an '08 model, it should still be covered by the BMW warranty provided you live in the USA. take it in and have them fix it. not safe driving with both systems deactivated.

yes, but why would you want to

once the ecu has been programed and encoded to the car you will have to make sure that the ecu has been aligned with the EWS control unit or it will not send a start signal to the starter motor

I bet the problem can be corrected by installing a new or repaired Transmission computer