20 Most Recent 2003 BMW 5 Series - Page 2 Questions & Answers

Hi Geno, You may have two different problems. The key does indeed have a rechargeable battery and you do not replace the batteries in BMW keys. Once the key starts failing, you probably need a new key. If you have another key, you can find instructions online to reprogram the key that is causing problems with the other good key. Try that first to see if the programming just glitched off. I have seen this happen. I also have had keys just go bad. The random flashing lights and quiet alarm are most likely due to a CAR battery that has a dead cell. I have had a number of BMWs on my car lot that will start and ACT like the battery is OK, but the hazard lights will randomly go on. Once the alternator charges the battery further, the lights go off as the battery is charged. I agree with Patrick D....make 100% sure the charging system and battery are operating within the manufacturer specs. Just because it starts and seems OK, does not mean it is. Hope this helps, good luck.

@01fordeb: You have to assume the system is dyed before a black light is useful.
Black light dyes are available [cheap] at any parts store.

asker: You may find that the coolant level sensor is defective, covered with gunk or that there is some static electricity built up in the coolant. A mechanic should know how to check for stray current. Also, it may be that a little fluid is going out the overflow because the wrong strength of radiator cap is on there, or the spring is worn out. Replacements are available at any parts store.

HOPE THIS HELPS! Don't forget to rat, please.

If there is wetness on pass sidefront , very well could be heater core issues. Start with replacing thermostat much, much cheaper. However dampness on passenger side is not good. best of luck

Your heater core is cracked and is leaking. You need to remove the dash and replace the heater core.

check the heater hoses in the engine are not leaking and the other hoses with the pressure up .as it can be your thermostat is sticking or the cap on your expanion bottle is sticking needing changed.

could be, or a loose connection or faulty motor

turn the key so everything is working but the car isn't started. then push and hold the little black button that resets the odo. while holding the button turn the key all the way back to the off. next time you start the car it should switch back to F.

Is there a way a mechanic can find out what's wrong with a 525i BMW if you can't read the OBC display because some of the the pixels are out?