General Red Warning Light Came On... Now No Brakes!

[Jpainter187]

Edit: make sure and read a few posts down.

I rode my Rockster to work this afternoon (the first time I've ridden it since the middle of last week) and after I was already on my way that the "General warning light" is staying on constantly. I am reading the manual and it says if it is staying on then the tail light/brake light is inoperative. But my tail light is on, and I tested both the front and rear and the brake light seems to be working fine.

Does anyone have any idea why this light would be on, since there seems to be no problem?

[omg1010]

Maybe a problem with the generator? You might want to check that the generator produces energy to charge the battery.

Best regards
Oliver

[Jpainter187]

I thought the light in question (the one w/ the exclimation point inside the triangle) only indicates that the tail/brake light inoperable when the light stays on constantly? Or at least that's what I got out of the manual...

[Jpainter187]

I'm officially POed! I went to ride to work today and the general warning light was still on, but also, the ABS test light would not go off and the servos were not working. Without the ABS it is EXTREMELY hard to stop! Can someone please tell me what my first step should be to try and troubleshoot this?

[iowabeakster]

Your battery may be the issue. This has been a pretty common occurance.

In addition to the warning of a burned out bulb, the ! light will come on when the battery is weak. The ABS system really wants to have strong battery. If during start-up, the voltage drops below a threshold it'll light the warning light.

Often times, if it is the battery, people will ride several miles to allow the alternator to give the battery a bit of a charge and warm up the engine. With a warm engine, the starter will draw a lower amount of current on start-up. Thus keeping the voltage in the "OK" range. Then, it'll work fine. Give this a try.

(the first time I've ridden it since the middle of last week)

Do you have a charger for it?

If the battery is on it's way out, Keeping it on a charger might allow you to get a little more use of the battery. A person who does a lot of short trips (less than 30 miles) is going to pretty hard on the battery. It'll never get a chance to recharge. A person who makes short rides should use the charger pretty regularly. With regular use of a charger, if this problem continues...your battery is on it's way out.

Even better...Do you have a multi-meter?

Test the voltage with the bike off...then with key on...then while pressing the starter button. That'll give you an indication of the strength of the battery.

If you need to replace the battery, get one of the best batteries.... Odyssey PC-680... or OEM BMW/Exide gel.

[Jpainter187]

I will definitely give it a shot tomorrow morning, since my shift tonight doesn't end until midnight. Thanks for the tips!

[sweatmark]

"General warning light" is staying on constantly. I am reading the manual and it says if it is staying on then the tail light/brake light is inoperative.

Could be iABS fluid level (both circuits have level sensor, with sensors wired in series). Folks here have had that fault due to worn brake pad(s) causing excess brake piston travel. Might just be low fluid though, or leak.

Could be brake switch fault.

Could be iABS servo module failure.

After you've confirmed battery status, check:

Brake light activation via each brake switch? (hand & foot)

Tail lamp ok?

Does iABS unit start up, whine, scream?

[Jpainter187]

Now that the rain has moved on I rode the bike to my parents house this morning (only about a 20-25 minute ride). I noticed the rear brake servo was still making the whining noise, but the front brake was not.

After having sat for a good 2-3 hours I started it up to ride home, and the red general warning light was still on (like it has been for the past few days) but both front and rear servos were working just fine.

After i pulled into the garage at home, I killed the bike and started it back up to see if the brakes were still working, but just my luck... The front brake servo did not past the start-up test and the ABS failure light was flashing at 4Hz. Also, I found out the previous owner had the battery replaced before I bought it. So this battery only has approx 600 miles on it.

What now?

[iowabeakster]

First off... sorry you are having these difficulties.

I'm kind of at a loss... as you describe these symptoms... the problems and the errors (as indicated by the lights) are not consistent and therefore hard to take a guess.

Do you know when the brake system had it's last fluid flush?

If your problem is just a solid lit "!" and servos are working (problem indicated in the first post, and again today)... then low voltage would seem to be the normal culprit. It could be a defective battery (even if it is a brand new defective battery). Do you know what kind of battery is installed?

OMG1010 sugessted the alternator... that could be another reason for low volatage too. Although, the alternators in these bikes have been very reliable. Also, new batteries should be charged too. Or else they will become old batteries quickly.

Measuring the voltage would be very helpful in troubleshooting.

I don't know if when the voltage is way too low that it entirely disables the servo system. That's unexplored territory for me.

But since, low voltage was the first indication... I would ensure of proper voltage.

Now why the servos work intermittently (and flashing light errors occur intermittently) ... that becomes really difficult. Intermittent issues are often electrical in nature. Have you removed the zip-ties here?

[Jpainter187]

I will go to my dads tomorrow and test the voltage. I'm unsure of the battery brand because I haven't ever removed the tank to check. In regards to charging the battery, is the auxiliary out (for heated vests, seats, etc.) always hot? I ask because if so couldn't I charge the battery that way by finding the correct plug and hooking my trickle charger to it?

Also, I did remove ONE of those wire tires when I installed my bar risers a few weeks ago because I needed more slack on the right side. So you suggest removing the one remaining wire tie? Oh, and I am unsure of the last fluid flush. I will also check the level tomorrow and let you know what I find.

[iowabeakster]

Yes, you can charge through the accessory socket. The battery should be the Gel/ AGM type battery (But, we don't know what battery it has...). If so, an old-fashioned trickle charger shouldn't be used, it puts out too much juice. And it won't shut down the charging when the battery is full... bad for the battery.

get one of these...you might be able to find them cheaper somwhere else. (This was just the first place that popped up after googling).

http://www.cyclegadgets.com/Products/pr ... em=BATTEND

Under the Battery Tender Plus... there are two choices...one of them is specifically for BMW gel batteries.

Or you could get the cheaper (.75A) Battery Tender JR. That's what I use. That's what my BMW dealer reccommended and sold to me. I got over 5 years out of my stock battery... and never once had a low voltage error on the ABS system. That is until I had absolutely no voltage at all. I use it over the winter... and when the bike might sit 2 weeks without use. Probably the more you use it the better it will be. Since it senses when the battery is fully charged and stops the charging, it won't cause problems.

If your bike has the external jump-start posts, that is an easy place to test the voltage without removing the tank or the starter cover.

Checking the fluid level on an ABS bike is more complicated than you might realize. There are 4 reservoirs. Two of them are on the ABS unit underneath the tank. That is probably not the issue since you have not gotten the alternating flashing light error code.

[Jpainter187]

Thanks for the heads up. I believe the previous owner had the battery installed at the BMW dealership, but will double check.

Can you describe to me where the external charging posts are, or is there a reference to it in the manual?

[iowabeakster]

Your bike may or may not have the posts (I don't know what year your bike is). You can purchase these from a BMW dealer and intall them, if your bike does not have them.

I made this picture just recently about jump starting... how convenient...

Red circle- positive post (has rubber cap on it)
Blue circle- negative post



Now, that I think a little... you could get a reading from the accessory socket too.

[Jpainter187]

Mine is an 04, and no it doesn't have those external charging points. I may have to buy them though cuz that would be much easier. After the cable guy gets here to setup the cable at my new place I'll ride to my dads and check the voltage. I started the bike last night when I got home from work ( about 12:30AM) and both servos were working, but still the general earning light. Hopefully (with everybodys help) we can get to the bottom of this, and soon!

Thanks guys!

[Jpainter187]

I forgot to mention that the previous owner emailed memback and said the battery is a universal powersports UB22-12N. So I guess he didn get that replaced at BMW...

And I misspoke about the charger. The one I use right now (I borrow my dads) is the Battery Tender Plus. I also found out the original owner installed a quick disconnect lead to charge the battery, but it's the kind with a dual side-by-side male/female connection. Correct me if I'm wrong, but isn't that what the Battery Tender Jr uses?

*Edit* Disregard about the QD plug. Just realized my dads Battery Tender Plus fits it also!

[Laserr Boy]

I had a very similar problem and it turned out that the switch at the front brake lever was the culprit. Remove the cover on the bottom of the right side grip, take out the screw that holds the micro switch and see if the servo comes on when you open and close the switch by hand, if it does then the problem is where the brake lever contacts the switch, if not follow the wire to the plug, disconnect and check continuity. Hope this helps.

[Jpainter187]

Well, after a complete charge and cutting the second wire tie shown in the diagram above I started the bike and rode it home. The brakes worked fine but the "!" light was sill on. Once I got home I let the bike cool for about an hour and started it again... This time no more warning light! I'm hoping the battery was the only problem. I'll make sure and keep it plugged in every so often so hopefully this doesn't happen again! Thanks again for everyones help!

[iowabeakster]

Jpaninter,

Well it sounds like good news, if not "completely perfect" news. Anyway... ...good to hear.

You said you didn't know when the last brake service was done. The wheel circuits have a recommended ANNUAL flush interval. The control circuits are every other year. You should look into getting that done. It's not an easy job, for a first-timer. It'll cost a couple hundred bucks at a dealer. A new ABS unit is about 2000 dollars... you really don't want to go that route... not at all.

I looked at the battery the previous owner had installed. It costs about 75 bucks. I paid 175 dollars for my new BMW/Exide battery in March. My stock battery Never (not once) gave me trouble like this. That is why I decided to stay with the same battery for replacement. The ABS system can be really fussy about what is a "good" battery.

[Jpainter187]

Yeah, once I get some extra money I will probably buy an original BMW battery.

I knew it was too good to be true... I spoke too soon because this afternoon when I started the Rockster the "!" light was back on!

*EDIT* About an hour later I went to pull the bike further into the garage because it was about to start raining and now the front brake servo is not working again either. I am going to contact the previous owner again and see if he knows when the last brake service was done.

[iowabeakster]

Man, I am sorry this is such a hassle for you...

Even though it seems like the brake/tail light is working... replace it. It is possible that it is defective but still illuminating. The worst that will happen is you will spend a couple bucks and have a spare. Also, clean the contacts in the bulb socket.

This just might be easier to take to a dealer and let them diagnose.

I believe (not absolutely positive, read it on the internet) that the ABS system requires a minimum of 10.2V or the light will come on. You need to measure the voltage and see if it drops below that, at any time (even while starting the bike cold). You will need to test the voltage while cranking the starter (cold bike), and with it running at idle just after start. Without those measurements, I don't know if we are just chasing our tail.

If the voltage drops below that threshold, first things to check...

connections at battery terminals...
negative battery connection to the frame...
alternator belt...
any added on wiring, lights, or accessories...