I remplace a new alternator and battery on a BMW x5 2001 it won'

Is the battery good?

I assume that the squeaky noise stops after 15 minutes, not the engine. If that is the case, you may have a very worn belt. This won't cost you a ton of money. You have a serpentine belt on your car, so that is a likely culprit. You may also have a bad battery, which in cold weather would perhaps have just enough to start the car but would also demand the alternator (and by extension, the belt) to provide enough amps to recharge the battery after a severe draw,
Before the winter, I recommend a new serpentine belt and a new battery, after a test of your alternator output and the battery at a good shop. You should not expect to spend more than $200 max, if everything is wrong.

The battery is good, so it would be either the cables to the starter or the starter itself.

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Key programmer software

If you had to replace the belt, it is possible that the battery didn't have a full charge 14.4v, should have been checked after repair

It could be that the battery is shorted, it could be that the alternator is bad, it could be that the alternator circuits have an open or shorted circuit, it could be something as simple as a loose or corroded battery cable end. It could even be a combination of things like a shorted battery that has damaged the alternator and BOTH need to be replaced. Or it could be even something more simple like a light or other accessory was left on and caused the battery to drain and all you need to do is jump-start the engine to get the battery charging and turn the accessory off. You must test your battery/charging system and/or check all of your electrical accessories to find out which it is.

Hi.

If it does turn over and electrical works, then the problem is unlikely the battery. You can try jump starting. If it cranks when jump-starting it may be a weak battery, starter motor or alternator, but I don't think that this is the problem.

Check if there is spark on all cylinders. Do a code scanning (this car is OBD1, you will need to do the scan at the dealer place or to find a BMW OBD1 tool- Universal OBD2 scanner will not work on a 1994 BMW). If the codes return misfire or mixture related errors check fuel pressure, check sensors and parts that determine the mixture (MAF/MAP, AIT, O2 sensors, IAC and EGR system), check the vacuum system for leaks and check the crank sensor.

Regards.

Ginko

check the alternator and wiring to battery. if belt is ok. then when car is off, voltage at battery should be at least 12.6 or better. when it is running, at battery should be at least 14.1 to 14.7. jump start car, try this, with car running, remove negative battery cable car should still run, if alternator is ok. if it quits when taking cable off,of battery. its the alternator thats bad. but if it run ok with cable off. then its your battery.

check the connection at the starter motor. that is the link between the alternator and the battery. BMW doesn't test properly from one end to the other.

that connection is ususally a heavy nut and it needs to be tight.

Need to test the battery ,and the alternator for a discharge .Was a new alternator used or a reconditioned one ?? ignore the lights for the minute because they sound as though the regulator is working ,iam more concerned about the diode pack in the alternator,hence was it a new one or a recon or one from a scrappers

the tensioner , have to retractit. Vitally