Car electronics shut off while driving??

[Prestovie]

So I was driving back from dinner, and on the way home there are some pretty choppy train tracks. Well I went over those, and about 500 yards away after a stop sign something weird happened. In the middle of driving, going around 30, my headlights started to flicker, my radio died, and my radar restarted. So I quickly yanked the radar and turned off the radio, figuring it was the battery. Lights slowly flickered back on for the rest of the way home(only another couple minutes thankfully)
Got home and parked it and it started right back up?
Anybody know what might've happened? A few weeks ago my battery died temporarily and took my car a couple minutes to start up, but this is the only instance since then.
Any help is appreciated, thanks guys.

[holyc0w]

Did you replace the battery?

Strange things happen when the battery needs to be replaced.

[fw_fw]

Definitely get that battery tested!

[fredo]

+1. Is it possible the terminals are a little loose ? :dunno

[az3579]

Have your alternator AND battery tested. Batteries don't typically die while driving unless the alternator has a problem.
Sounds like some sort of a ground issue, be it with those components or with something else.

[Prestovie]

Ok so I took it to Autozone earlier today and had them run a diagnostics for free(yay) and they found out my crank shaft sensor was misfiring, part number P0335
Said it was a $45 part, unfortunately didn't have the money on me at the time so I had to drive home without it.
Anybody have experience w replacing/fixing this? I looked into it and it doesn't look all too confusing to find and remove

[fw_fw]

OK, they read the codes, but did they check the battery and alternator?

I wouldn't think that the CPS would affect dash electrics....

[GotZHP]

My guess is battery, alternator, or voltage regulator. I had something kind of similar happen to me last week. Driving down the highway all is fine, then my radio stops working. Thought at first it was an issue with my phone that was hooked up to the AUX cable so I tried the CD. No volume. Then many warning lights came on (Brake, abs, traction control), then some of my gauges stop working. Pull over, shut down the car, and try to restart, wont fire.

I had already replaced alternator and voltage regulator, so I bought a new battery and things are back to normal.

Bimmers do weird things when there voltage is off, so Get your alternator & battery tested. First go to fixes. Could be as simple as a loose connection.

[az3579]

Ok so I took it to Autozone earlier today and had them run a diagnostics for free(yay) and they found out my crank shaft sensor was misfiring, part number P0335
Said it was a $45 part, unfortunately didn't have the money on me at the time so I had to drive home without it.
Anybody have experience w replacing/fixing this? I looked into it and it doesn't look all too confusing to find and remove


While that could still be a problem, that probably isn't what caused the symptoms you describe. A bad crank position sensor would cause drivability problems. Your car was running fine when all this happened, right?

[Prestovie]

Ah jeez haha alright yea that makes sense, I'm gonna end up taking it into my local dealership to have a full diagnostics done. If it's the alternator I'll cry lol, I can handle it being the battery or voltage regulator though. I'm glad I didn't buy the sensor then, $45 still in my pocket
I'll keep you guys posted, thanks so much for the help

[fw_fw]

Ah jeez haha alright yea that makes sense, I'm gonna end up taking it into my local dealership to have a full diagnostics done. If it's the alternator I'll cry lol, I can handle it being the battery or voltage regulator though. I'm glad I didn't buy the sensor then, $45 still in my pocket
I'll keep you guys posted, thanks so much for the help

I would take it to an Autozone and have them test the battery & alternator for FREE before you go to the stealer, as the dealer will find 15+ things wrong with your car, if they are wrong or not. If you do have to go to a dealer to get something done, you need to walk in knowing what the car needs and to be informed, as they love an uninformed customer walking in the door.....

[Prestovie]

I would take it to an Autozone and have them test the battery & alternator for FREE before you go to the stealer, as the dealer will find 15+ things wrong with your car, if they are wrong or not. If you do have to go to a dealer to get something done, you need to walk in knowing what the car needs and to be informed, as they love an uninformed customer walking in the door.....

Good idea, I've got an autozone about 20mins away so I might even get out there today. If it is the alternator, what kind of figure am I looking at/how long would an install take? Batteries I know are like $300 and not difficult to replace

[fw_fw]

Good idea, I've got an autozone about 20mins away so I might even get out there today. If it is the alternator, what kind of figure am I looking at/how long would an install take? Batteries I know are like $300 and not difficult to replace

$300 battery??? From the dealer installed cost maybe. Autozone should be battery $150-175, and they install for free. Alternator start around $275 for a refurb and go up from there, plus install costs if you don't DIY...

[slater]

Good idea, I've got an autozone about 20mins away so I might even get out there today. If it is the alternator, what kind of figure am I looking at/how long would an install take? Batteries I know are like $300 and not difficult to replace

OEM batteries are $225 CAD + tax (13%) here in ontario from BMW, it should be quite a bit cheaper in the US ($175USD i would assume).

[Prestovie]

$300 battery??? From the dealer installed cost maybe. Autozone should be battery $150-175, and they install for free. Alternator start around $275 for a refurb and go up from there, plus install costs if you don't DIY...

Awesome, good news after good news :biggrin gotta love autozone, no more shopping at O'reily's haha

[fredo]

Im pretty sure Autozone will not install the e46 battery, because it's in the trunk.

[ELCID86]

Im pretty sure Autozone will not install the e46 battery, because it's in the trunk.

That's odd. Had not heard (or thought) of that.


Sent from my iPhone with TaT.

[BMWCurves]

As Fredo said, they won't install it because it's in the trunk. I tried at my local Auto Zone earlier this year.

[holyc0w]

:confused

I checked under the hood. There's no battery :dunno

[Prestovie]

As Fredo said, they won't install it because it's in the trunk. I tried at my local Auto Zone earlier this year.

Well shoot, how difficult is it to install the battery? Or do I actually have to take it into the dealer?

[GotZHP]

$300 battery??? From the dealer installed cost maybe. Autozone should be battery $150-175, and they install for free. Alternator start around $275 for a refurb and go up from there, plus install costs if you don't DIY...

I just paid ~$165 for a battery from a dealership! That is a huge rip off. Install should be in quotes as it took 5 minutes to swap the old for new

[holyc0w]

No dealer trip required. Here's a DIY video on a touring. The process is pretty similar. Sockets required might be different on the sedan.
https://www.youtube.com/watch?v=beN2L0TFmPU

Also:
http://www.pelicanparts.com/BMW/techarticles/BMW-3-Series-E46/03-BASICS-Battery_Connection_Notes_and_Replacement/03-BASICS-Battery_Connection_Notes_and_Replacement.htm

[GotZHP]

Well shoot, how difficult is it to install the battery? Or do I actually have to take it into the dealer?

On a scale of 1 to 10 with 10 being the hardest, its a solid 1.

Go to trunk and open. Lifting trunk floor up and pull the black plastic tray on your right out. It will have the side carpet / upholstery thing going into it, so some force will be required. Loosen the tie down, two bolts either 10 or 12mm. Move tie down out of the way. Disconnected battery by removing leads. Again two nuts, either 10 or 12mm. One thing I almost missed isthe plastic breather tube. This will be on the side of the battery facing the front of the car. Simply pull the tubing off the battery. MAKE SURE to keep hte black plastic elbow piece as the new battery will not come with one.

reverse the steps above and bam, new battery in 10-15 mins for a new guy. Any questions PM me. Just did this last week.

[Prestovie]

On a scale of 1 to 10 with 10 being the hardest, its a solid 1.

Go to trunk and open. Lifting trunk floor up and pull the black plastic tray on your right out. It will have the side carpet / upholstery thing going into it, so some force will be required. Loosen the tie down, two bolts either 10 or 12mm. Move tie down out of the way. Disconnected battery by removing leads. Again two nuts, either 10 or 12mm. One thing I almost missed isthe plastic breather tube. This will be on the side of the battery facing the front of the car. Simply pull the tubing off the battery. MAKE SURE to keep hte black plastic elbow piece as the new battery will not come with one.

reverse the steps above and bam, new battery in 10-15 mins for a new guy. Any questions PM me. Just did this last week.

:rofl Thanks so much for the help man, appreciate the step by step. Any recommendations on battery brand? Or should I opt for OEM?

[GotZHP]

:rofl Thanks so much for the help man, appreciate the step by step. Any recommendations on battery brand? Or should I opt for OEM?

I tend to normally go with the OEM option but that is because I get killer pricing at the dealership near buy. In this case I am sure a battery from Autozone will do just fine. It will be around 200 from there vs the 300 from the dealership, so 100 saved for later maintenance.

[Prestovie]

I tend to normally go with the OEM option but that is because I get killer pricing at the dealership near buy. In this case I am sure a battery from Autozone will do just fine. It will be around 200 from there vs the 300 from the dealership, so 100 saved for later maintenance.

Nice, thanks again I should be able to go sometime this week hopefully. Also for some reason now my "Service Engine Soon" light actually turned off after all of this, so idk if it fixed itself or what haha, but that light has been on since I bought it

[BMWCurves]

:rofl Thanks so much for the help man, appreciate the step by step. Any recommendations on battery brand? Or should I opt for OEM?

I got a Duralast Gold 94R-DLG from Auto Zone. More CCAs than factory battery, and was cheaper (about $180).

[az3579]

I got a Duralast Gold 94R-DLG from Auto Zone. More CCAs than factory battery, and was cheaper (about $180).

I think it's that one that only lasted me 2 years. :(

[az3579]

I got a Duralast Gold 94R-DLG from Auto Zone. More CCAs than factory battery, and was cheaper (about $180).

I think it's that one that only lasted me 2 years. :(

EDIT: Nope, it was the 49DL that lasted only 2 years. Just passed Year 3 on the 94R-DLG.

[Sheepdog84]

Funny thing that this thread should pop up.... I don't entirely mean to hijack it, but I had a VERY similar issue.

Last night, I was driving (cruising at 80 on the hwy), everything operating normally, and....
My zhp's electronics started to turn off one by one (cruise control, dash lights, radio, etc) and it eventually came to a sad, dead, stop.

Tried to start it again after waiting a few minutes. Engine *eventually* starts and runs, but as soon as you turn on the headlights, ABS, DSC lights come on- making it unsafe to drive. Red Battery light comes on also.

Earlier this month, I replaced the voltage regulator on my alternator, which brought my voltage up to the correct levels (13-14v when idle then revving).

Before I left my car, I ran the onboard diagnostic voltage test... and even just at idle, my car was only getting 10v!! :eyetwitch

And without a doubt, i know that can't be right. My battery is new(er), but not old by any stretch.

Could the alternator have failed? Could the voltage regulator I so lovingly DIY'd, have failed?

Kinda hard to say without testing.

Any thoughts? I'm considering taking it to an indy bmw shop nearby to have it checked out.. I just don't want to if i dont have to :(

Thank you!!

[Dual]

Further jacking- I've been dealing with intermittent loss of the rear defroster. The dashboard light will go out and I have to turn the defrost back on.

Just in case anyone has some input...

[az3579]

Further jacking- I've been dealing with intermittent loss of the rear defroster. The dashboard light will go out and I have to turn the defrost back on.

Just in case anyone has some input...


It turns off after a certain time. This is normal.

[Sheepdog84]

Quick update:

I first swapped the voltage regulator, which didn't exactly improve my results- still at low voltage, car would die pretty quick.

Went ahead and did a whole new alternator swap in a parking lot- all good now! 13.5v+ and charging the battery as it should.

Super thankful for the huge e46/ZHP community out there. I learned a ton this week.

[danewilson77]

Quick update:

I first swapped the voltage regulator, which didn't exactly improve my results- still at low voltage, car would die pretty quick.

Went ahead and did a whole new alternator swap in a parking lot- all good now! 13.5v+ and charging the battery as it should.

Super thankful for the huge e46/ZHP community out there. I learned a ton this week.
Win. Well done.

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