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2002 BMW battery problem

My 2002 BMW 525 failed to start today. When I turned the key, it felt like the starter is clicking and most of the lights are on but it just won’t start.

I checked the battery (it is the original one) and its indicator light is still green. It says on the battery if the color is green, it is still OK. Only when it turns black or yellow the it is bad.

With nothing else I could do, I went ahead to do the jump start. It worked. The car started after a couple minutes of jump start.

I had similar problems before. Last couple times I brought it to the dealership and they said fauly swithes remained on which drained the battery but the battery is still good after the recharge ( I guess he looked at the same green indicator light too).

I am very puzzled by the facts that the car needs to be jump started even though the battery indicator is good and all the lights are on and the starter is clicking etc. Could this really be a battery problem or something else?

After you jump it and drive it around for a while, when you turn it off can you immediately restart it? Is the charge light on? If not, you almost certainly have a bad battery. I’m not quite sure how those battery indicator lights work, but I think they will only show a totally dead battery, as opposed to a battery that’s merely getting too weak to turn your motor over, which is what you’ve got. 6 years is pretty much the end of the life span even of a very high-quality battery.

The clicking means that the voltage is low going to the starter. It may be the connections to the battery are dirty so you should clean then even if they look ok. Use a battery post cleaning brush.

The sight indicator on the battery isn’t reliable. The battery may be weak even if it shows ok. A voltmeter will show what the truth is.

You should never, ever put your faith into those battery indicators. I’ve seen more than one with a green eye and junk status.
Your original battery is probably now going on 7 years old since the car was more than likely built in 2001 and it’s had a good life.

I don’t know how the dealership is testing the battery but looking at the color of the eye should not be one of the factors. The battery should be charged for at least an hour and a load equivalent to 3 X the starter current draw applied for 15 seconds. At the end of that time the battery should be at 10.2 volts minimum.

That indicator is just an indicator of low electrolyte. If it is green it does not need water if it is red it needs water. It does not indicate that the battery is good bad or charged.

Since you have a 2002 battery, it is time to replace it, especially since it appears it has been drained a couple of times by “faulty switches.”

It certainly would be a good time to clean the contacts as well. Most places will do this as part of replacing the battery.

Note: while the dealer can replace the battery and will likely do a good job with a good battery, you likely can get as good or better battery elsewhere with equally good service for less money.

Change the battery before a dead battery won’t let you into the car at all! Many auto parts stores will sell you a battery, and install it for free.

I never cease to be amazed at how many people will keep a battery in their car long past the reasonable life-span of the battery, and despite warning signs that the battery is beginning to fail. Yes, batteries are known to fail without warning, but in this instance, the OP has had more than sufficient warning that his 6-7 year old battery is failing.

For the grand sum of ~$60. (maybe even less!), you can get a new battery and have confidence that the car will start reliably for the next 4 or 5 years, rather than continuing to fool around with jump-starting and visits to dealers and mechanics. In my opinion, time is as valuable a commodity as money is, and continuing to waste time with jump-starting and visits to mechanics is just poor economics when the solution is as cheap as the cost of a new battery.

As I mentioned I had the similar problem 6 months ago. The dealship checked the battery at that time and they said the battery was OK (even though I told them I suspected the battery was bad). I have no problem replacing the battery, but what if there really is another mulfuction device that is draining the battery?

You need to determine if the battery is really at fault, there is a connection problem to the starter or, the starter itself is bad. By checking the voltage at the connections to these areas while the trouble is occurring you can determine what is causing this problem.

But if the starter is bad, it won’t be jump started, right?

BTW, do I need a deep cycle battery as what the dealership told me to have?

You should not need a deep cycle battery. Car batteries seldom need to deep cycle and when they do it usually damages the battery, doing it too often will kill a battery. That can happen when you have something burning power with the ignition off. It appears the dealer is telling you they don’t know what the real problem is so they are suggesting a battery that will be harder to damage. Generally it is better to use an automotive battery in a car.

I’m having the same exact problem with my 1995 525i. On a cold morning in Feb. it was cranking but it didn’t turn over. I thought it was the battery so I had it towed to a mechanic, who the next day was able to start it. I had him check for spark, change the fuel filter and replace some of the spark plug boots just to insure a tight seal on the spark AND I replaced the battery myself. Just a week ago, two months after starting well and running perfectly I took my car out to lunch and it was a warmer than usual day and after leaving it for 5 minute in the parking lot it didn’t start. Had it towed to the same mechanic, let it sit for a day and he was able to start it, I even left the car with him for a week and he said it started everyday.
This issue isn’t a bad battery problem since I have two month old battery in my bimmer. I’m beginning to think that this issue has something to do with a bad temperature sensor, the starter solenoid or the fuel pump. I checked many of the relays in the electrical boxes, cleaned up the relay connections but they seem to be working fine.

Talking about the same problem. Yes, it’s me again. I replaced the battery and after running for a little more than a week. It died again today without any warning sign! I went to pick up my kids today (it is about 70 degree out) and parked my car outside of the school. By the time I came back (5 minutes), it just would not start and the battery appeared to be dead (an one-week-old battery). This time I can’t not even jump start it. With the jumper on, it regained some power (a few lights came back on this time) and started to click (it would not even click before that) but still would not start. One strange thing was the security system went off evry time I opened the door or pressed my key remote, and I couldn’t turn it off. The security system was pretty much the only thing that was functioning (or not). I can’t believe a car that was running fine 5 minutes ago and now it is completely dead. I had to have it towed to the dealership (the tow truck guy told me only the dealer can fix it).

I suspected, before I replaced my battery, that something else other than the battery was wrong. I am afraid it is true. Any idea what could be the problem?

Step one, have the new battery charged and tested (load tested). Then have the cars charging system tested. Is the alternator working properly? Then have them do a “parasitic load test”. This will find what is draining your battery. It is usually the useless security alarm system. Just have them disconnect it. You can live without the cute little chirp it gives you…

It’s very possible that you had another problem besides the battery. An old battery can cause other problems.

While it seems that this is seldom done, when I first trained as a tech decades ago I was taught that anytime a vehicle has an electrical problem an entire system check should be performed. The customer was charged .5 an hour labor for this chore (cheap IMHO). It went like this:

  1. Charge battery minimum of half hour/check cable ends.
  2. Perform battery load test.
  3. Perform starter load test.
  4. Perform alternator output test.
  5. Check for parasitic draw on the battery.

I’ve always stuck to this and it kills all of the birds with one stone and leaves nothing to chance. This saves guesswork and detects all problems at one time.
Sadly, I think you will find very, very few shops (either dealer or independent) that will do this.

Due to the time involved charging the battery, taking up stall space, and doing the actual testing, most shops will more than likely make an educated guess rather than do all of the footwork. To me anyway, it’s peace of mind and worth losing a bit of time over.

The dealer said it is caused by the failed ignition and general module. They did not say anything about the alternator. I think I will ask them to do all the tests and make sure no other problems.

“The dealer said…”

Dealers are no better (or worse) than independent mechanics for almost anything you might need done on your car.  They will almost always charge more per hour and often more for parts and supplies.  They also tend to look at repairs a little different than the independent. 

A dealer may well recommend work that strictly may not be needed, but could be connected to the problem or maybe replace a part when a little repair would fix it ALMOST as good a new.  

I suggest that most people would be better off finding a good independent (Not working for a chain) mechanic. 

Note: Never ever use a quick oil change place. They are fast cheap and very very bad.

Someone told me since the cars are so computerized nowaday, only the dealer will have the equipments to plug into the car and find out what was the problem, e.g. the fault memory stored in the car that could give error messages or hints.

A failed ignition module is a separate problem from the battery and when someone told you that only the dealers have the proper equipment, etc. to diagnose the problem they were wrong.

By replacing the failed ignition module was the problem solved?