BMW X5 BATTERY DRAIN, HOW TO TEST ALTERNATOR DIODES BMW X5 E53 E70 F15If you have BMW X5 and you need to test the alternator diodes because you have battery The lack of refrigerant is the cause, the IHKA system will see the logic from the pressure switch and begin to work if there is enough refrigerant in the system, it won't require a reset. A/C systems require special tools and equipment to be serviced correctly. They also operate at high pressures and repairs should be done by trained technicians. I put the brand new beast battery from the M3 into the X5 and it slightly improved the lowest voltage possible at idle up into the mid to low 12's (still not satisfactory I think) and cruise RPM charging is still in the 13's usually around 13.7.. Maybe a little low.. Not much change, effected no other symptoms.. Before testing the fuel pump, go over this checklist. This includes some obvious items and often forgotten common maintenance issues that may turn into a false "bad fuel pump" diagnostic. 1. Check for fuel in the tank. If the engine cranks but refuses to start, make sure that you actually have fuel in the tank. 2. engine shut off after low oil pressure light came on. Asked by samanbmw Jan 11, 2016 at 09:45 PM about the 2009 BMW X5 xDrive30i AWD. Question type: Maintenance & Repair. i have 09 X5 3.0 and message on the dash is said low oil pressure and I put oil in it then it said oil level ok, but after driving few miles message came back and car turned The most common symptoms of a bad blend door actuator include abnormal noises, incorrect climate control outlet temperature, and varying outlet temperatures. Electrical faults and damaged gears are some of the reasons why the blend door actuator can fail. A faulty TCU on the BMW X5 can result in a battery drainage problem. Issues with the TCU on the X5 are prevalent, which ultimately causes the battery to drain. Usually, the TCU or Telematics Control Unit is located in the trunk, in almost all BMW X5, and would be hidden by the trimming. The TCU mainly controls –. You need to turn your ignition key to the accessory position when the lights and radio come on (that is before starting the car). You need to press and hold the “Trip” button on the instrument panel until the red light comes on. Next, press the Trip button a second time and then hold until Reset appears. X5 Battery Drain issue (I'm running out of ideas) SHORT VERSION: I replaced my alternator and the battery died while I was driving. The battery shows that it is charging whenever I test it at home with the car on. The battery voltage changes when the positive battery cable on the distribution box is moved around. This light should light up for 2-3 seconds when you turn on the ignition but then go away if the immobilizer has communication with the key. If the light stays on, it means that you have a problem with either the immobilizer control unit or the transponder key. 2. Trouble Starting Your Car. While difficulty unlocking or locking your car points EtfzCfg.