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Yet another battery light question... >:(

3K views 15 replies 5 participants last post by  euroE28M5 
#1 ·
Hi everyone.

Haven't posted in a while so here it goes..

BTW, before posting I did look through the forum for answers with out any luck..My case is slightly unique??

So I got a 2003 E46 330i sedan.

With colder months approaching my car started acting up a little bit.

First it would take a little while for it to actually start, the cranking.. Then as the temps dropped to like -5 Celsius I got battery light on.

So after driving it for like 5 minutes it disappeared. I should also mention I live from work like 5 minutes away.

Point is this happened for a week.. I however never had to boost the car.

So the following week same stuff, solid red battery light.. Driving it to work and the traction control lights came on, air bag light, as well as E-Brake light and it was flashing orange and red... Again after making a detour it was gone again... This happened for a couple of days in a row as well..

Now since the first occurrence I had a feeling either battery or alternator is going... But it started every time... and the lights were gone soon after driving the car for a bit..

I did the test on the weekend to check if my alternator was working... YUP. Works fine. Doing it's job. (ALL THANKS TO THIS FORUM AND ITS AWESOME PEOPLE ON THE WRITE UP ON HOW TO PREFORM THE TEST)

The other day again same symptoms came up.. so I got to work and just driving around the parking lot hoping to charge my battery.. All of a sudden my headlights go out.. Again At this point I think the battery is really R.I.P so I parked the car and went in to work.

Since I work for a Toyota dealership i decided to try and use a Toyota Battery with better CCA. 690 instead of the previous CAA Battery that was in there that only had 650 CCA.

SUCCESS!! It starts so much more smoother and better!!

So now, when I start the car in the morning and its not even cold.. I get a red solid battery light for a little bit.... After driving it.. It goes away...?? Whats the issue here?

Is it my short 5 minute commute to work? The battery doesn't get enough recharge? Although driving it to work the engine barely warms up to its operation temperature So I have to take a detour to get that warmed up as well..

Please advise,

Thanks in advance.
 
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#2 ·
Okay lot's of bad things here.
1. All those error lights turned in because your battery voltage was low. The E46 hates low battery voltage.
2. Your engine must be in a tin of pain. Your oil gets contaminated when it doesn't get fully warmed up. Even when the temp gauge is in the middle, it's only 60 something degrees Celsius. The car's operating temperature is 96 degreed Celsius
 
#4 ·
Learned something new today.. Did not know that when the temp is at 12 it doesn't mean it is fully warmed up.. Thanks,
 
#3 ·
Assuming the car has the original alternator it is 14 years old at this point. Brushes wear and I had a problem with my X5 where it would not charge when first started cold, I would let the engine run about 2 minutes, then restart the engine and then the regulator would start working.

The regulators are easy to replace on these alternators and fairly reasonable in price.

But also not your driving conditions probably will require a monthly battery maintenance recharge. A 5 minute drive is not good for any car, especially in the Winter months. You mention you take a detour to warm the engine up fully, you do realize it takes about 3 times as long for the engine oil to come up to temperature in these cars and the temp gauge is buffered so the engine is not always very warm when the temp gauge is at 12 o'clock.

I assume the replacement battery is new? I would have it tested just to make sure it is fully charged and good. A weak/bad battery would give you the symptoms you described with warning lights to come on and so forth.
 
#5 ·
I've read about the brushes and I was thinking of doing that. Yes I do know that 5 minute drives aren't good for any car..What I did not know was about the temp, if its at 12 it does not mean it is fully warmed up. The battery is new as far as I know, Definitely should check if it is not damaged/drained. Thank you.
 
#9 ·
Mileage is 250K Km. But I did the test.. The alternator is working.. Why would I replace it?
 
#12 · (Edited)
You certainly are in the range where the alternator could need replacing. Your description seems to indicate an intermittent issue, that mostly occurs when the car is first started. With the engine running you should never see the battery light. And calling it a battery light with a battery symbol is actually very misleading. It really has nothing to do with the battery. It's indicating the battery is not being charged (alternator issue).
 
#14 · (Edited)
You certainly are in the range where the alternator could need replacing. Your description seems to indicate an intermittent issue, that mostly occurs when the car is first started. With the engine running you should never see the battery light. And calling it a battery light with a battery symbol is actually very misleading. It really has nothing to do with the battery. It's indicating the battery is not being charged (alternator issue).
I appreciate your help. But again why would I replace a good alternator if it is doing the job. Voltage is good.. Like I said I really do think it is my short commute to work.. Regardless. If anything i should replace the brushes/regulator if anything..
 
#15 ·
PROBLEM SOLVED I THINK? Basically drove the car for a while last night.. Started the car up today, no light no problems!! I really think the whole problem was my short commute to work. I really appreciate all of your help guys!
 
#16 ·
***UPDATE***

Problem occurred again. First intermittent red battery light then it was solid. This happened for a few days.. Car ran fine and everything worked. Today was the day the alternator died - Like many of you have said that it might be the problem. All electronics started shutting down one by one. Car died on the side of the road roughly 7 mins from my house.. Thank god that didn't happen this past weekend on my way back from Montreal... Because those symptoms started occurring 250Km from Toronto...

Thank You for all of the help!!!!!

If I can give any advice to others.. Check battery first.. if that's ok replace the alternator/brushes/voltage regulator.

CHEERS!!
 
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