02 X5 (3.0) won't start!

[mattcarlgray]

I have a 2002 X5 3.0 that I have had to jump start on four occasions over the last 30 days. I had the battery tested and it's good (only 6 months old). When the car sits overnight there isn't enough power from the battery to start the car however, I can't jump it off and drive it for a while and it will start right back up. I do have an external Sirius radio but I unplug it for the power source so that can't be the problem. The car does have Nav if that system could be pulling the system down? Looking for help.

Thanks, Mark

[gwinder]

Are you leaving the key in the ignition? Even if it's not in the on position, the car sees they key so it keeps the system active which will drain the battery. Also, even without the key in the ignition, it does cycle through the alrm system which can also drain. i had the same issues with mine until I started taking the key out of the ignition at night.

Gary

[BrianX54.4is]

Hi Mark, I'm new here but I'm feelng your pain! Only in my case the car needed a jump start almost every morning! I've been a real pain in the a** to the neighbours! Once started the car would stop and start all day but left overnight, the battery (only 5 months old) would drain and it was the toss of a coin as to whether or not it would turn over the engine the next morning!

I was sure there must be something not shutting down and continuing to pull power when the car was locked up. My mechanic advised he sucessfully cured the same kind of problem on 2 other X5s by replacing the heater fan resistors so we went for that. A €100 later and the problem was still no better. Then we put the old resistor pack back in the drivers side and replaced the passenger side pack with the new one - still no joy. He was out of ideas now so a friend recommended an auto electrics outfit not far away.

I arranged a visit and he checked the battery load with an clip-on ammeter. We fooled the car into thinking the tailgate was closed by shutting the lower flap and actuating the lock on the upper tailgate. We locked the other doors/armed the alarm. The raised luggage compartment floor sheilded the motion sensor from us so we wouldn't trigger the alarm. Now the car was as if it was locked up as normal. The current showed 3.5 amps - a major drain. However after about 5 minutes the current dropped off in stages down to 0.5 amps - this is normal current.

He then asked me what battery was fitted (you can't see without first moving the active suspension compressor housing). I told him it was a 100ah Banner Starting Bull. "Ahh Banner" he said - those are crap batteries and notorious for poor reliability! "I'm 25 years at this and I've seen so many issues with these". So convinced was he that the nearly new battery was the problem that he offered to replace the battery with a Hella 90ah (as OEM and spec'd by BMW) and if I was still having the problem - he would refund the Hella no quibbles. We fitted the Hella and he checked the charging was ok with engine running and high load on (all lights, demister, heater fan on full etc.) he was happy with this. He said to run it for a month to prove the case and then return the Banner to the supplier and demand a refund (glad I kept that receipt!)

It's early days to know for sure but so far the engine bursts into life every time and after all, the amp test proved the cars load was normal when shut down after 5 minutes.

Never would I have suspected the 5 month old battery! BTW the previous battery was also a Banner - it failed suddenly last September, ok one day and dead the next, wouldn't even take a bench recharge of 10 hours. The date on that one was October 2004 just 3 years old at the time! Not much of a lifespan.

Your Battery could still be your problem although not yet failed as severely as mine and still passing a battery test. If you carry out the drain test as above - you can rule in or out the cars electrical systems as the culprit.

Hope this helps,
Good luck , Brian

P.S. Gary - nice to live in a place where you can leave the keys in the car! In my neck of the woods you need a ram bar in the driveway!

[EKS PYB]

Originally Posted by BrianX54.4is

P.S. Gary - nice to live in a place where you can leave the keys in the car! In my neck of the woods you need a ram bar in the driveway!

Tell me about it! I have never not even once left my keys in the ignition and i've lived in this country for 22 years. Whether it was a Ford, a Mitsubishi, a Lexus or a BMW.

You must really live in a very safe neighborhood. Even with a locked garage I still lock my cars and take the keys with me to the bedroom.

It definitely must be nice Gary!

[jayjay_dee]

so how about ur alternator?