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Discussion Starter #1
Hi everyone,

I'm new here and unfortunately my first post will be a cry for help. My 2008 EOS 2.0 TDI took me by surprise today - when trying to start it I noticed that:

1) the symbols on dashboard which normally go off after a few secs stay lit
2) a new "airbag fault" warning appears
3) a repeated clicking sound can be heard all the time the key is turned
4) all the lights (footwell, dashboard etc.) appear to dim every time the click is heard
5) starter motor won't move at all when the key is turned further into the "start" position

I initially thought it might be a weak battery and tried the jump leads but to no avail. Any thoughts??

Thanks,


/h88
 

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point 5 is the key - starter is jammed - maybe a tap with a hammer to free the solenoid (the big bit sticking out side - tap it on end gently...) or may need new/ recon motor... any warranty with it?
 

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Discussion Starter #3
point 5 is the key - starter is jammed
Nah... I should have made it more clear that 1)-4) happen also when I don't even think of starting the engine. I just made a second visit to the car which got stranded 1 mile from home and now whenever I turn the key (= ignition on), something starts clicking repeatedly (every 1 sec). And it's not just the starter motor which doesn't get any current, it's also electric windows which I can't close, lights, MFD and everything else. I tried disconnecting the battery for a few minutes but it didn't help.

:mad:


/h88
 

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Sounds exactly like a failed battery to me, they fail quickly and the symptoms are just like you describe.

Adam
 

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Yep, my battery went dead and car went crazy. No signs of failure either. Dealer replaced, but said the factory battery normally will only last 2-3 years. Car has high electrical usage and a lot of on board electronics that are sensitive to voltage changes.
Lopaka��
 

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Yep, my battery went dead and car went crazy. No signs of failure either. Dealer replaced, but said the factory battery normally will only last 2-3 years. Car has high electrical usage and a lot of on board electronics that are sensitive to voltage changes.
Lopaka��
Thanks for this one and the other two hints. I initially thought of the battery being flat but then why starting using jump leads didn't help? (my naive thinking perhaps) Shouldn't the electronics have gone back to normal when I connected the flat battery to the healthy one in the other car?

If all the electronics have gone mental, will it suffice if I just buy a new battery and replace it, or do I now need to take the car to the dealership for some computer lobotomy or something?

Thanks again,



/h88
 

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Jump leads may not be powerful enough.
 

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If your battery is flat you will need heavy duty jump leads (as used by the break down guys) to to jump start a diesel engine (or a heavy duty jump pack). You may also find that constantly trying to turn an engine over with a faulty battery can cook your starter motor. Mick
 

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Update: Eos safely back in driveway

I managed to jump start and drive back home. The key point was stick to my guns in terms of how to connect jump leads rather than listen to a helpful passer-by who "worked in a transport company and jump-started many trucks in this way before".

The only problem I have now (which also drained the battery in the first place) is some large fans running all the time in the front of the engine compartment, just behind the front "grille" thingy with VW emblem. I don't even know what those fans do, this is the first car of mine with which I'm not at all familiar... A temporary solution was to disconnect the "+" battery terminal after shutting down the engine but clearly something's not right.

Thank you very much for all the replies, they indeed saved the day last night! (saved the night, should I say? ;) )


/h88
 

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Do you have air con? If so one of the fans are probably to do with the air con system (they are on my other Cab). The common fault is that the fan relay/s fails and keeps the fan/s on but they normally go off when the igintion is switched off so that they don't cause a drain. The engine fan runs on after the key is removed if the engine is running hot due to being in heavy, slow moving traffic.

My EOS engine temperature seldom exceeds 90 degrees and I do not recall being aware of the fans running after the engine is switched off.
 

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Exact Same Problem

I'm having the exact same problem as the initial post, i went to start my car after to weeks of being idle and the dashboard just went crazy! airbag problems, lights, windows the lot, window is now stuck half way down and won't move! after reading all above comments, i tried charging my battery and replacing no joy, tried to get it jumped, again no joy, although they arnt great jump leads. The only thing different than the original post is the starter motor does begin to move but then nothing.

When you manage to jump your car off did you use bigger jumps leads, also do we think just buying a new battery will solve this problem?

regards peter
 

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Why don't you guys and gals with these types of problems go and buy a cheap digital multimeter? After all you have already bought an expensive car. :(

You clip the probes to the battery terminals and measure the voltage, then follow a number of scenarios of putting loads on and repeating.

http://www.vweosclub.com/forums/showthread.php?t=14930

Whenever you jump start a modern car full of electronics you take risks. In fact, even starting it with a totally dead battery is a big risk because the alternator is capable of producing high level damaging pulse spikes which are not smoothed by a flat or faulty battery.

Once you start seeing those kind of random dash light problems you need a known good battery and diagnostics to help you. By 'clutching at straws' you can do more expensive damage. But then there are plenty of old school mechanics that will tell you to hit things with a hammer first!

You could make sure the battery post terminals are clean and check the engine/chassis grounding post.

Whenever you try to start a car with a low battery (<9V) there is a high chance the starter relay contacts will weld themselves together and hold the starter on. :eek: Somebody can work out why that might happen.
 

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Sounds like a dying battery to me. Mine went a few years ago. One day the car was fine, the next day the dashboard was flashing like crazy.

Autozone diagnosed a battery issue, replaced it, and everything was fine.
 

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................................................

Whenever you try to start a car with a low battery (<9V) there is a high chance the starter relay contacts will weld themselves together and hold the starter on. :eek: Somebody can work out why that might happen.

Hi voxmagna,

The answer is based on basic electrical theory - Power = Amps x Volts.

The power rating of the starter motor is effectively constant so if the voltage is decreased, the amperage has to increase. The cause of the welding is the fact that the heat generated by an electrical current is a function of the amperage squared [increasing the amperage by 10% will generate 21% more heat]. If the voltage decreases to a point where the motor will not turn, the amperage will try to increase to the motor Locked Rotor Current value until the battery fails or the motor windings burn out. The contact welding is usually avoidable collateral damage from trying to run the starter motor for an extended period of time to start the engine after the battery voltage begins to drop - 15 seconds is the longest I would allow the starter to operate before switching off before trying again; if unsuccessful after 4 attempts, it is essential to allow the starter to cool down before further attempts. The modern geared starter motors are more tolerant of abuse than the old direct drive starter motors but they still can fail from electrical overload just like the older starters.
 

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I managed to jump start and drive back home. The key point was stick to my guns in terms of how to connect jump leads rather than listen to a helpful passer-by who "worked in a transport company and jump-started many trucks in this way before".

The only problem I have now (which also drained the battery in the first place) is some large fans running all the time in the front of the engine compartment, just behind the front "grille" thingy with VW emblem. I don't even know what those fans do, this is the first car of mine with which I'm not at all familiar... A temporary solution was to disconnect the "+" battery terminal after shutting down the engine but clearly something's not right.

Thank you very much for all the replies, they indeed saved the day last night! (saved the night, should I say? ;) )


/h88
By now it is obvious to everyone that this thread and the OPs problems are old enough to have mold and hair growing on them.

However, by now, I hope he knows better than to disconnect the positive battery cable as opposed to the negative cable.

Did I hear an explosion?!!

Has anyone ever heard from him since? :eek:



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..................................................

However, by now, I hope he knows better than to disconnect the positive battery cable as opposed to the negative cable.

Did I hear an explosion?!!

Has anyone ever heard from him since? :eek:

The following photo shows what happens when the positive cable is disconnected whilst a battery is charging [the same thing will happen when discharging] as the disconnection is always accompanied by sparking. This is not one of my efforts but comes from a car club friend from Vancouver B.C.


 

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Hi voxmagna,

The answer is based on basic electrical theory - Power = Amps x Volts.

The power rating of the starter motor is effectively constant so if the voltage is decreased, the amperage has to increase. The cause of the welding is the fact that the heat generated by an electrical current is a function of the amperage squared [increasing the amperage by 10% will generate 21% more heat]. If the voltage decreases to a point where the motor will not turn, the amperage will try to increase to the motor Locked Rotor Current value until the battery fails or the motor windings burn out. The contact welding is usually avoidable collateral damage from trying to run the starter motor for an extended period of time to start the engine after the battery voltage begins to drop - 15 seconds is the longest I would allow the starter to operate before switching off before trying again; if unsuccessful after 4 attempts, it is essential to allow the starter to cool down before further attempts. The modern geared starter motors are more tolerant of abuse than the old direct drive starter motors but they still can fail from electrical overload just like the older starters.
Well I was just testing to see who would come up with the correct answer - very close Silvershadow :) but I will add the answer I was looking for:

Most starter motors could be taking around 200 amps when they are cranking normally with the correct battery voltage. In the case of a pure resistance that follows Ohms Law, reducing voltage normally reduces current. But these are d.c motors with brushes and commutators that switch the current as the motor rotates. The 200 amp motor current taken when loaded and cranking is an AVERAGE current with 12 volts.

When the battery voltage drops, the fully loaded motor has insufficient power to keep its commutator turning at the correct speed. Therefore each very low resistance coil on the rotor spends less time switching and more time sucking current, causing the average current to increase very rapidly. Manufacturers will rate their starter relays for around 200 Amps with some overhead. But low battery voltage could push the starter relay to handling 400 amps+ and the contacts may weld together. Some oems build a low voltage detector circuit into their starter relays. When battery voltage hits 9 volts or below, the relay will chatter or pulse on and off as designed. It is not always the battery doing it, but it can play havoc with the rest of the vehicle electronics.

Most make the mistake that a low voltage battery means it gives out less current. In the few seconds that a starter is cranking, there will still be plenty of current to cause relay damage.

The worst risk to starter and relay comes during winter morning cold starts. Higher mechanical loading on the starter and lower cold battery voltage and efficiency.
 

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I must now correct some misconceptions about disconnecting positive and negative battery cables. It makes little difference to explosion risk if you disconnect the positive OR negative first whilst the battery is charging - sparks and arcs can still occur at the negative terminal.

Explosions arise because the battery could be giving off loads of HYDROGEN and as we all know from the early history of airships, hydrogen only needs a static spark to cause an explosion.

When you need to disconnect a charger from a charging battery you should SWITCH OFF AT THE CHARGER WALL SOCKET first. The second point is that chargers should not allow the battery to overcharge and gas, when far more hydrogen is released.

Returning to the misconceptions, removing the negative lead first and replacing it last is a safety procedure you follow when installing and removing vehicle batteries and has nothing to do with avoiding sparks setting of hydrogen.

Most will be using their standard open or ring spanner wrenches to remove battery terminals. The car body metal work is grounded to battery negative on most cars. Therefore if you start releasing the positive terminal first and your uninsulated wrench touches it, there could be a loud 'bang' and in the worst case the wrench welds to the bodywork and your battery explodes in your face! :eek:

By removing the negative terminal first, you reduce the risk of shorting the positive terminal to the chassis and the risk of life long disfigurment which your wife would not like.:( When refitting a battery you reverse the procedure by fitting the positive terminal first, then the negative terminal. Of course they do put batteries in plastic insulated boxes, but most 6-9 inch wrenches can find some metal close by.

I have now wrapped some red insulating tape around all the wrenches in my toolbox that fit the battery clamp bolts.
 

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Hi voxmagna,

I tried to keep my explanation simple so a non-technical person could understand what was happening. This is a legacy of my professional career where I frequently had to explain complex technical issues to non-technical decision-makers.

With regard to a battery explosion whist connecting/disconnecting a battery, the picture I posted earlier is worth a thousand words. Fortunately, the Darwin Award candidate who disconnected the battery miraculously was not injured by projectiles or ejected battery acid.
 
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