I have had this x5 as the wifes dd since 2012 or 2013 and it had been a great purchase, especially after i stupidly got rid of my 99 540i6. So car has been great, more power then we need, tight, every once in a while i need to run it hard as the wife dont or it will slightly miss out. I have been fighting this problem since 10/31/2015 where the car would not start with no crank randomly, most of the time it would put it in TFP. After 10/31/2016 we stopped locking the car to see if the anti theft was locking out the starter. I cleaned the ignition sometime around christmas. I think its the transmission switch as a couple of times i have gotten it to start my messing with the shiftier but i cannot find any information on the 6hp26 zf transmission switch and how to test it. Most of the time when it would not start we would just wait for the car to sleep and it would start fine, however this week it is not starting a lot even after waiting. It had shut off twice while moving slow speeds, once on 10/31/16 and once around 2/17. I ordered a crank sensor from bavauto but it was not the correct one, the part number i pulled out of my car is 7 503 140-05 and i am having trouble finding one. I dont like to throw parts at a car i rather troubleshoot it. I have been thinking about getting auto engenuity with the bmw package to perform in depth troubleshooting, has anybody used this and could it find whats causing a no crank? Car probably has the common valve seal leak and the oil filter cap leaks a small amount as well, i have been topping up with mobil 5w30 at first with one quart, then one quart of 10w30, and a quart and a half of 15w50. Probably have around 5 to 10k miles on this oil. It is a 12/4 build 2005 x5 4.4i, i am probably forgetting other information but i am lost on what to do please help.

10/31/2015

the car went into engine failsafe and transfailsafe while I was turning (sadly normal, not bmw fast turn) and shut the engine down. Was 3/4 mile from my mothers house and called her for a tow as it wouldnt crank. When she got there, maybe 5 minutes, it started with trans failsafe. We hung out few hours and drove home in TFP. I cleared the code,

p0335, crankshaft position sensor A circuit

p1727, (no description, but points to ambient temp sensor if i recall)

with my scanner, torque pro with bluetooth adapter, and all is well. Looked into it on the forums and thought i might have had a low battery or a bad crank sensor. Left the batter unhooked overnight and charged it up. Battery is approching old, but is not.

So all is well untill

12/23/2015

i thought i only had the same two codes but my screen shot shows,

p0335, cranks sensor

p2088, Powertrain A camshaft Position Actuator Control bank1 b

p2090, Bcamshaft bank1 c

p1727

With tons of pending faults, honestly i dont remember all these but it is in my screens

p111F, p0261, p0270, p0267, p0264, p0598, p0102

So i do the same again, fine untill 2/04.

p0335, p1727 with p11f pending.

2/17/2016

same three codes

3/3/2016

I left the fill cap half on and half of and got a slew of codes, car ran rough, i put the cap on right and cleared the codes.

3/9/2016

p0014, B camshaft Position

p0335, p1727

pending, p0300, p0306, p0308, p0303

3/22/2016

p0335

p0024, B camshaft

p1727

3/25/2016

happened today, no crank, while i was driving, well car was parked while we wre eating. Held key in start position and moved shifter back and forth, heard clicking in the ignition when going into park. I do not think its a transmission switch. I checked voltage from ob2 adapter and it read 10.8. Got a jump from family and it would not try to crank untill the voltage read on the ob2 adapter around 12.2 volts, which took about 5 minutes of booster cables being hooked up. It started and voltage read running at:

Ob2 adapter, 13
Obc, 13.8
Jump terminal, 14.4

I am going to check the electrical connections at the starter, ground strap, battery, and battery acident cutout. I will be also most likely replacing the battery. I beleive i have two separate issues, one being the ews low voltage lockout and a bad crank sensor, i think i have to change the pigtail to the new style on the crank sensor.

4/1/2016

Car wouls only last 1 day from a full charge. Wife drove it when i said it was not a good idea and it shut off going over rain road tracks. I jumped it and drove it back watching voltage on obc. Was around 13v and would drop to 12v on a bump consistently.

4/2/2016

Checked voltages everywhere, had 12.4 volts when car is asleep, 12.2 awake, key off both times. Checked voltage and tightness at jumper post, battery, battery cut out, battery ground. Checked voltage at alternator and connection looked tight. Checked connection at power steering and was tight. Checked immobilizer fueses and had 11.8 key on and engine off. Was working to check the starter but quit for the night.

[B]Would like to know what you guys think, how one removes the alternator on a n62, where is the voltage regulator, should i check connections under the dash where the jumper wire from the hood connects too and how you get there? Any help appreciated thanks![/]