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This is the continuing saga of my wife's 2004 Beetle. I have re-registered under my actual name and was formerly oliver28472. The beetle returned home yesterday after a month and a day at the dealer. It was the third time there for a discharging battery. If interested, please refer back to the old thread under the same title started by someone else who has had the same problem. My dealer was given a copy of that thread so they could check out the car as prescribed by John Koch. The battery actually did die on them one time. They still don't know why. They said they did everything that was suggested on the thread. No parts were replaced. Obviously I am not convinced. I told the s.m. that we can't keep doing this. It's time to look up the lemon law.
 

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I cannot find any of the old posts about your problem in a search of the old forums. Can you include a link to the original post, or describe the symptoms of your problem again? It is unfortuante that the forum software upgrade broke the link to all the old posts. Perhaps with some info the cause of the problem can be found. There is likely to be an intermittent current drain on the battery with the key out of the ignition--it just has to be tracked down.
 

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my turbo is bigger!!!!!!!
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mine had an imoberlizer problem.. it would eat batterys like skittles... i went threw 7 b4 i found the problem
 

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Dick, my mistake, the title of the old thread is "Battery goes dead". the last post was 9-14-05 by John Koch.

Ed
 

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It is unfortunate that your particular VW dealer is unable to perform the necessary troubleshooting to determine the root cause of your discharged battery. Actually, cars are not "lemons" -- it is the dealer service departments and the car maker's technical assistance systems that are the real lemons.

You don't show your location in your profile. I live in central Indiana. If you live close, I have equipment to troubleshoot this kind of problem.

There are 3 basic causes for a dead battery:
1. The battery is defective
2. The alternator (generator) in the vehicle cannot provide a charging current sufficient to keep the battery charged, or
3. There is a parasitic drain on the battery when the engine is off, draining the battery. Any parasitic battery drain can be there constantly or less likely, it occurs only intermittently.

If you have a battery charger (even if it is only a trickle charger), connect the charger to your battery when the car is sitting in the garage to prevent a parasitic drain from discharging your battery. A prolonged low battery SOC (state-of-charge) will shorten the life of the battery.

Did the dealership service manager describe any details of how they determined whether the root cause is item 1, 2, or 3 above? Typically, if the battery can be recharged and when charged it can pass a battery load test, it is likely to be OK.

If the battery has been recharged and the system voltage is 14 volts or higher at any engine RPM above idle speed, the alternator is likely to be OK. There are more sophisticated alternator output checks that can be made if you use a clip-on amp meter to check charging amps out of the alternator.

Troubleshooting a parasitic load on the battery requires a clip-on DC (direct current) amp meter that has resolution to about 0.05 amps. These meters typically use Hall Effect sensors or you can use the more expensive Swain DC amp clips (http://www.swainmeter.com/index.html). The Swain DC amp clip that I own costs about $800 and is probably not something that the average dealership service department has available to it. These DC clip-on instruments allow you to simply clip over a wire carrying DC current and the current flow in amps can be directly measured by the instrument.

A typical Beetle will have a parasitic current drain on the battery of no more that 0.06 amps (all doors closed and unlocked). This magnitude of current drain would easily allow your car to sit for 30 days without use and still crank and start. However, if the current drain increases to 0.15 amps, your car will likely not start after 11 days of no use if the battery was fully charged when the engine was shut off. Any typical relay that is continuously energized will draw about 0.15 amps. A battery drain of 0.5 amps which is typical of a glove box lamp will drain the battery to the point of a no start in just over 3 days.

Most of the electrical loads in the Beetle are isolated from the battery by either the ignition switch and/or the load reduction relay (relay 109) when the ignition switch is in the OFF position. Therefore, the most likely causes of a run down battery include the modules controlling security, door locking, trunk unlocking, the engine control computer, cooling fans, etc. These are examples of loads that are "awake" when the key is not in the ignition.

Your dealer must be able to measure DC current flow as describe above to isolate the offending electrical load. If a battery drain is detected, fuses can be pulled one-at-a-time to determine the circuit that is drawing the current. If your present dealership service department does not know how to do this, you need to find another one.
 

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Sharp answer that is right on target Dick Larimore. Actually any digital multi-meter, even a cheap model can be used to measure paracytic drain. It must be a digital type to pevent damage to many sensors and circuits that cannot take any input or they could be damaged. The multi-meter is of course attached between the disconnected negative cable and the neg. terminal of the battery. All electrical items are off. The alarm may be left armed to duplicate a normal off and resting at park condition for the car. The test can be run either way, but with the alarm system which is a component of the comfort module on, you maybe able to detect a high current draw with it on and then check with it off to see if it is really off and not using any power. There are a multitude of associated components, sensors, switches, ect. in the comfort module that start at the door locks and the power unlocking system, hood lock, rear hatch lock, antenna, window electrics, fuel door opening motor, mirror adjustment switch, horns and interior lights. I am probably missing a couple of attached and interfaced items...Fortunatly, this comfort module can be scanned and each and every item in it can be checked, including any connections if that is indicated. If the current draw matches any known draw of a specific item, then tracking it maybe easier. 0 to 100 milliamps drain is normal for our cars. If the drain test is inconclusive at pin pointing the exact item, then the multi-meter is used to check voltage accross a fused link, the actual circuit, switch and connector starting in the fuse box located on top of battery case. The fuse panel inside end of dash on drivers side should be checked then and after that, the fuse and relay box under the dash just left of the steering wheel, behind the knee trim panel is checked. If all circuits are being tested correctly, then the drain, a short to ground, or a shorted out switch that stays on all the time can be found and repaired. Any VW dealer should be able to trace and repair this with a bit of labor and alot of persistance and a logical understanding of the basic cars electrical system...Good Luck to Ed Hall.. He is at a disadvantage with a VW service department that cannot find this problem. Obviously they do not have a qualified electrical tech. that knows the basics of electrical circuitry and how a negative ground system works..Keep trying. Maybe VW of America should know about this dealer that cannot fix their product. JK
 
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