Last night rapid flashing indicators. Battery Flat

[baldsparky]

Following from another thread (Dreaded rapid flashing indicators) I tried to get into the merc today with the transmitter and NOTHING.
Battery is now stone cold flat.
Obviously somethings been drawing current overnight, but after the initial problem when locking up ie indicators rapid flashing everything seemed fine.
Apparently even if there is an alarm horn battery fault, the indicators flashing does time out, it that correct ??
Certainly the alarm didnt go off, and I kept checking the car and indicators had stopped flashing so now its all down to what could be causing the battery to completely drain.
Any suggestions will be appreciated. Batteries on charge right now

 

[Dec]

What year is the car?

Dec

 

[baldsparky]

1st registered november 1999. 51000 miles full history immaculate with all the toys working when I picked her up 4 days ago.
Its one of the first new shapes if that makes sense.

 

[Dec]

Fast flashing of the hazards means the alarm is triggered, the siren should also be sounding, if the siren is not sounding then it needs to be replaced, it may have been flashing all night, on and off, with the resulting flat battery.

When triggered, the siren should sound for about 20 seconds and the fleshing should time out after 2 minutes

The siren is the brains of the alarm and costs about £80, only from dealer.

Is the car battery the original factory fitted or has it been replaced since new?

Dec

 

[baldsparky]

Its certainly a mercedes battery, not sure of its age though. Looks brand new but that goes for the whole car. When charged I will see whats going on. The car started and ran like a dream when i bought it 3 days ago. Even yesterday it started on the button after standing for two days.
Be nice if there was some way of knowing how old the battery is.
Certainly thinking of replacing it just for peace of mind.
I have quite a bit of electrical knowledge, so my guess is the battery drain is very recent and coincides with the alarm problem.
Have owners had problems with batteries being flat as a result of a failed alarm horn unit ?
What kind of current drain is normal with the car just standing ?
Im thinking of series linking the positive terminal through a DC amp meter to see what kind of draw is present.
Obviously I cant turn any components on during the test because current draw will be limited to what the amp meter can handle (about 10 amps)
Thanks very much for the advice Dec.
I still prefer the Merc over the Jags ive owned despite this set back lol

 

[baldsparky]

One other question. Is there a fuse I can pull that kills the supply to the alarm horn. If thats the gremlin at least it will stop the battery running flat until i get a replacement.
Just being lazy, I know the other option is to disconnect from under the left wing.
Many Thanks

 

[Dec]

Don’t know if you have a fuse or not, if you have, try pulling it if its not sharing with some other component.
To be sure, it’s best to unplug the siren, pulling the fuse might disable the alarm but might not stop the alarm draining the battery… remember this is a faulty electrical component, you never know what it might do.

Or

You can unlock the car with the remote, this should disarm the alarm, you can then lock the car manually with the emergency key blade inside the remote, this will leave the car locked but with no alarm security.

These alarms usually die at about 10 years old, yours may have been faulty for the last few years but with no symptoms until now.

Anything over 50ma then there might be a drain. I think the faulty alarm is what drained the battery, unplug the siren, with the car unlocked. You cant really do any tests as the alarm is faulty, if you unplug the alarm then you wont really be getting a true reading as the alarm is absent.

I wouldn’t change the battery until you see signs of problems, nothing in the car history about the battery?

Your car is referred to as a W220, see… Template:Mercedes-Benz vehicles - Wikipedia, the free encyclopedia

Dec

Edit ,See also... http://mbworld.org/forums/sl-class-...goes-off-no-reason-kills-battery-fix-diy.html

 

[baldsparky]

Many Thanks Dec
I will report back when I have an outcome.

 

[baldsparky]

Quick update
Just noticed the following onfo on the battery 100 AH 3601-0100-1

And most important
Date 21-03-13.
So unlikely to be the battery me thinks.

 

[AL3X]

Possibly rear Sam if not the alarm...

My 08 c63 had an intermittent fault with fast flashing indicators, and a warning of "rear turn signal bulb fault' yet all were working!
Then the battery started to drain, turned out to be the rear SAM! Although I had more issues than that

 

[baldsparky]

Possibly rear Sam if not the alarm...

My 08 c63 had an intermittent fault with fast flashing indicators, and a warning of "rear turn signal bulb fault' yet all were working!
Then the battery started to drain, turned out to be the rear SAM! Although I had more issues than that

Excuse my rookie ignorance AL3X whats the rear SAM stand for ??

 

[Ted]

Signal Acquisition Module.

 

[AL3X]

That's the one!

As far as I'm aware it's attached to the rear fuse box in the boot, I assume your car will have one too but I may be incorrect...

 

[baldsparky]

I managed to replace the horn siren under the front wheel arch today.
I split the old unit and it was full of battery liquid, poured out of the thing.
For sure the internal rechargeable batt as had it.
Hopefully this will turn out to be the reason for
A) My indicators rapid flashing a few minutes after i lock the car.
and
B) The reason for the cars battery running totaly flat by the next day.
Battery will go back in her fully charged tommorrow.
Fingers crossed.

 

[baldsparky]

Battery is now back in.
Car has come to life with everything functioning as should.
There were loads of messages scrolling through the dash and suggesting I vist the workshop.
I did the full steering lock left to right thing, and the car decided a workshop visit wasnt required after all.
Everything back to normal phew !!
After a nice long test drive, I parked her up and set the alarm.
Chirp,chirp,chirp, audible, along with flashing indicators in unison with the chirps and silence. All set, lovely jubbly.
So definately the alarm horn was an issue.
All I hope now is that after leaving the car standing for a couple of days she will still have a charged battery.
If yes, problem solved if no, then I have another problem to sort.
Watch this space, and thankyou so much for the good advice regarding the alarm horn cus guys, you were spot on with that one.

 

[1945wickedred]

Just get yourself a CTEK trickle charger from Amazon and all will be well and of course a new alarm siren as well,I had the same problem during last winter,got my new siren from local MB dealership and got a friend to fit it so all ok now.

 

[baldsparky]

It WAS the alarm horn.
I have left giving a conclusion for a few days to see what the eventual outcome was.
I am pleased to report that the inherent fault would have (by now) totally drained the battery.
This morning (fingers crossed) I tried the the car after standing for a couple of days.
Plenty of go juice in the battery, problem solved.
Many thanks for all the advice on this great forum, couldnt have pinpointed this without you.
Hopefully,despite being a rookie. My experiances and this outcome can add in a positive way to other owners of this great car, who may share a similar problem.
Many thanks once again.

 

[Dec]

Thanks for the feed back, its useful to others with similar alarms, these alarms have about the same life span as a dog.

The alarm usually never gets tested by the owner, the little flashing alarm light is no guarantee that the alarm is working properly, and a proper test should be done regularly and if there is a battery drain, it’s the first thing that should be checked, the siren is getting power all the time regardless if the car is locked or unlocked.


Dec

 

[baldsparky]

Another question on this subject, the answer to which could be usefull to many.
If the car is in a secure area, and your confident about locking it manually with the key, rather than the transmitter.
Would this prevent the alarm from activating. (I noted that the dash switch led doesnt flash using this method)
Im thinking in terms of if the car was parked up for long periods without having the luxury of a ctec connected.
Would this method reduce the amount of normal battery drain ?
Or is the fact that, because the alarm is (as you say Dec permanently connected to the electrics) it really wouldnt make any difference what you do.
Just a thought.

 

[Dec]

The metal key blade is for emergency entry into the cabin or the boot in the event that you have a flat battery or there is a failure of the central locking system or the remote fails to unlock the car.
It is very important to check that the key blade will open the door or boot and that these locks are lubricated and tested regularly throughout the year, if this is not attended to then these locks can seize up due to lack of lubrication and use.

Also, the key blade can be used to lock the boot so that it can’t be opened with the remote or the cabin boot open switch, this is called valet mode, where you want to prevent access to the boot by persons who have been given the remote to access the car, without the key blade the boot cant be opened. See separate locking of boot in your User’s Manual.


-When you lock the car with the lock button on the remote, you arm the alarm… Red LED flashes on alarm switch… if you then open a door or boot with the metal key blade when the alarm is armed then the alarm will be triggered…this is normal.

-When you unlock the car with the unlock button on the remote…Red LED OFF on alarm switch…you disarm the alarm, if you then lock or unlock a door and or boot with the metal key blade the alarm will not go off as the alarm remains unarmed.

-The metal key blade is solely a mechanical means of locking and unlocking the car and has no electric function, also called the emergency key. If the car is broken into then alarm will not be triggered. Your car is/maybe insured on the basis that it has a working alarm so if it was stolen / damaged the insurance are unlikely to cover the theft/loss part of your insurance.

Not sure what the current drawn by the alarm is but it’s probably (guessing) something like 20 milliamps armed and 15 milliamps disarmed, the total current draw on the battery might be about 40 milliamps with other? consumers like the clock or whatever is on when the car is locked up, apart from the alarm, so a healthy battery should be good for about month with the alarm on… depends a lot on whether the weather is very cold.

In your own particular case you should keep the alarm armed and lock in the usually way with the remote, provided you are sure the battery is fully charged, not a lot to be saved by leaving the car unarmed.

Note, just because a battery is new, if it is not fully charged then the car is parked up then it might only survive some? days before the battery goes flat.
Conversely, if a car battery is old but fully charged it may not preform as well as a new battery, an old battery can be quicker to lose its charge and so may not last as long as a newer battery.

One other point, if the car battery goes flat or if the alarm is unplugged, while it is armed, it could cause the alarm to go off as the system thinks it’s being tampered with, notable in your case, as the faulty alarm siren caused the battery to drained and so the alarm was triggered, albeit just with flashing lights and no noise due to the siren fault… the final convulsions of an alarm that’s about to die.


Dec