Red Battery & Transmission emergency mode Symbols today

dalekressin · May 11, 2011

Odd day today.
My 2001 530i got to work and a co-worker asked why I had the windows down and the moonroof open as rain was predicted. Hmm surprise to me. This has happened in the past and I thought it may be due to keys in my pocket.

Well they did that on their own. So I closed them all without problem.

I was leaving work and on the highway at ~75 mph the car hesitates very slightly and I saw a red battery symbol on the left. Pulled out the owner's manual and it stated stop and get to BMW dealer.

Moments later yellow circle with numerous lines appeared in yellow on right side below temp gauge. Yeah temp gauge was straight up. The symbol in manual indicated transmission emergency mode.

I got off the highway and soon noticed reduced power and the car coasted to the road side.
All indicators went blank as did the speedometer. I checked battery terminals and they were tight. The trunk light was lighted. No luck in finding a loose battery terminal.

The car was towed to a safe location where a friend will flatbed the car home ~65 miles.

Any ideas on diagnostics?
I wonder how bad this will hurt?
Advise appreciated as usual.

Vin M · May 11, 2011

Sounds like a charging system issue, or your battery is shot.

If you can get the car started again, you can check the charging system with a volt meter.

13.5 Volts at idle is normal.

Above idle it should be 14.3 Volts.

If it drops below 14.2 volts (above idle) it might be an indication that there's a problem with the alternator keeping a consistent charge (maybe a bad regulator)...also, check the belt for the alternator as well.

The battery should hold a 12.6 volt charge when the car is off, however, that may drop considerably while cranking the engine over if it's weak.

The best way to test the battery is to charge it up and perform a load test, your local auto parts store (I.e. AutoZone, Pep Boys, etc.) will usually do this for free.

granlund · May 11, 2011

My first guess would be the voltage regulator is starting to give out. If you have not done so already, unlock the OBC and read the battery voltage in 'test #9' per instructions: http://www.ideaphile.com/bmw/540-obc.html

dalekressin · May 11, 2011

The OBC info is great.
I might get a new battery and try that when I get the car back today.
Hopefully the car will start. It was very evident I lost all power as the speedometer and all meters dropped to zero as I coasted to the side of the road.
All suggestions welcome.

Josh P. · May 11, 2011

The window thing sounds battery related. However, I'm not sure the car would go to trans failsafe mode because of a bad battery or voltage regular while underway. This sounds more like an alternator issue, but let is know what you find.

granlund · May 11, 2011

With the completely computerized cars since the last ~ten years, when the charging voltage drops, pretty much ANYTHING is possible in terms of weird faults.

If the battery is ten years old, then yes, it's probably a good idea to replace it. Otherwise I'd look at the alternator charging voltage.

Another problematic point is the power steering fluid reservoir that is prone to leaking from the hose fittings - directly down on/in the alternator with not so good consequences.

bmw_n00b13 · May 11, 2011

Alternator died... whether it's belts or rebuild time will be determined by the mechanic I'm sure. Don't be scared by the transmission failsafe. It's voltage related.

cn90 · May 11, 2011

Jump the battery:

1. If the car runs fine for 30 min, then alternator is fine.
Replace battery as necessary.

2. If car stalls after 15-20 min with red battery light, then alternator is dead.
Check alt output with a voltmeter.
Of course, in this case, you need new alternator.
Or rebuild the alt yourself, info in forum.

dalekressin · May 11, 2011

Cn90
That is my exact plan.
I'll be back with a report.
Thanks to all of you for the support.:thumbup:
I apprec iate your time & efforts.

dalekressin · May 12, 2011

OK here is the finding...

The car started up right away but died within 10 minutes.
Alternator belts fine.

Now I will use the search button to learn about rebuilding the alternator.
Is it a bad idea to get a rebuilt alternator from Autozone????:dunno:

OR

Do I need OEM alternator???

granlund · May 12, 2011

dalekressin said:
OK here is the finding...

The car started up right away but died within 10 minutes.
Alternator belts fine...

Did you read the voltage when the car was running? It should be ~13.5-14

dalekressin · May 12, 2011

OK,
I found this with the search button:

My 2002 M54's alternator failed last August at 94K miles.
- One users' example of total electrical failure (AAA towed away) alternator repair (1)
It was a Bosch 120A original alternator (see pic)
I replaced with a $200 remanufactured Bosch 120 from OEM Bimmerparts
Working fine at 98K miles
Next time I'd plan ahead and stock the $30 parts to rebuilt it myself
See Cn90 explanation of why you want to rebuild your own alternator (1) & where to obtain the hard-to-get bearings (1)

I'm planning to look around more.

dalekressin · May 12, 2011

It was a driving rain when I picked up the car and we were in the open air.
I did not check voltage. Sorry if this seems stupid.

If the voltage was 13.5 to 14 after the start up before the car dies, does this indicate the alternator is working adequately?
There was no evidence of belt slippage. The lights quickly dimmed before the death.

If this is not alternator, what is rapidly causing battery discharge?

granlund · May 12, 2011

If the voltage is 13.5-14 after the car has started, the alternator is charging the battery. It is possible that the alternator would stop charging a battery, for example when the voltage regulator at the back end of the alternator warms up. This would be indicated in a dropping voltage just before the engine stalls.

Also, if the battery is old, it may not be able to maintain a charge for very long (even just a minute) and then it would make the car near impossible to start without booster cables.

bluebee · May 12, 2011

I must commend the OP for finding on his own the references!
So, I'll do more work than usual to give him pointers (since I've been there myself).

It sure 'sounds' like your alternator, but read this thread to be sure:
- How to test a BMW E39 battery & alternator (1)

BAD ALTERNATOR (see red battery light):

GOOD ALTERNATOR (you don't see the red battery light). Notice the SES which is discussed in the thread.

If it 'is' the alternator, then you will want to consider the following:

Physically, determine exactly what alternator you have (1)
- The Bentleys will only provide a clue
- You'll need to actually look, to be sure
If you have time, stock the parts for a rebuild (you'll need 'em eventually)
- Cn90 explanation of why you want to rebuild your Bosch alternator (1) & hard-to-get quality parts (1)
- Aioros 1999 Valeo Alternator rebuild DIY (1) and quest for quality materials (1)
Consider doing the entire belt drive system:
- Physically, determine what type of tensioners you have (1)
- Determine which parts you need to buy for a complete drive belt system overhaul (1)
- Do the alternator and drive belt system DIY (belts, tensioners, pulleys, rollers, alternator) (1)
Consider doing the entire cooling system system:
- Physically determine the date of your cooling system (1) (2)
- Determine the cooling system overhaul parts (1)
- Consider buying or making the optimal fan clutch removal tools (1)
- Do the cooling system overhaul before the time bomb goes off (1)

Here are additional links you may need for the cooling system overhaul:
- What to look for when your KTMP (1) or coolant temperature gauge indicates overheating (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) & what to look for in a perfectly normal E39 cooling system (1) & a picture of every failed part in the cooling system (1) & various techniques to properly bleed (1) (2) (3) & refill (1) & drain (1) (2) & what coolant to use (1) & what parts to replace (1) (2) & what special tools to make or buy (1) & how to tell how old your cooling system is (1) (2) & how to test the cooling system auxiliary electrical fan (1) (2) & a DIY for replacing the auxilliary fan (1) & the infamous fuse 75 (1) & the aux fan relay (1) & how to diagnose lack of HVAC/IHKA heater core heat with cooling system (auxiliary pump) at idle (1) & a Behr radiator and Behr/Heat expansion tank autopsy (1) (2) & request for another Behr surge tank autopsy (1) & why new made-in-China Behr/Hella expansion tanks are DOA (1) & E39 Fan shroud removal DIY (Besian) (M54) & some of the better cooling system DIYs (cn90 1997-1998 M54TU) (cn90 V8) (aioros '99-03 M54) (Ågent99 '01 530i) (pelican 3-series) (bluebee M54B25) & tricks to replace the fan clutch nut (1) & lower-hose thermoswitch o-ring (1) & to non-destructively remove the heater hoses (1) or radiator nipple (1) or expansion tank nipple (1) (2) or Oetiker clamp (1) or misplaced thermostat wiring loom (1) or broken bleeder screw (1) & modifying the cooling system pressure cap (1), or using propanol-based zero-pressure fluids like NPG+ (1) (2) (3) (4) (5) or all-aluminum cooling system parts by Zionsville (1) (2) (3) aluminum radiators & what happens if you drive one mile too far with an overheated BMW cooling system (1).

Karbon · May 12, 2011

Had almost the same issue as you, dale.
Ended up being the alternator. I ended up getting a re-manufactured Bosch 120A put in and it works fine. 1 year or 12k mile warranty on it.

dalekressin · May 18, 2011

Ok Bimmerfesters, you all saved me again. Alternater is back in and up and running. Reading Blubees link saved me (again).
THANKS so much.

dalekressin · May 19, 2011

The alternator was full of debris from steering fluid and leaves from the air intake.

bluebee · May 19, 2011

I added that quote to the battery & alternator DIY testing thread to help others.

My alternator also suffered from the same two 'avoidable' ailments.

Power steering drips from the hose
Leaves blocking the air ducts

Do you think the power steering fluid and the leaves blocking the cooling ducts are 'probably' the worst 'avoidable' enemies of the alternator?

There is a cn90 fix for the power steering hose ... but I don't know if anyone suggests clearing out the alternator ducts periodically.

Do you know of any way to clear the debris without removing the alternator?

Here is a picture of the debris (not mine):

dalekressin · May 21, 2011

Wow, mine did not look that bad.
If possible, I will keep my cars in garages to avoid some of this.

granlund · May 21, 2011

They are road bugs. The only way to avoid it is to not drive the car at all.

Red Battery & Transmission emergency mode Symbols today

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