Bad Battery, Fuse box, or Alternator??

I was driving the car yesterday and noticed when trying to use Cruise Control that it would flicker on and off not allowing me to use it. I drove the car later that day and cruise control was back to working again. I parked the car last night, all lights and controls off, and went to drive to work this morning. When I turned the key the dash lights and radio started as normal however when I turned the key over to start it just clicked and everything went off and now the car is completely dead. No electric power whatsoever.

I understand that this is a very common sign of a dead battery but my questions arises from the fact that the battery is barely 1 year old and hasnt shown any bad symptoms until now.

Any ideas? Maybe check the battery voltage and the fuse box that is notorious for burning out?

Thanks in advance!

Just because its only a year old does not mean it cant go bad. Youll have to get it checked, and then you can check if the alternator is putting out 13.5 (approx.) volts when running.

If the alternator wasn't working right you should have had the light on the dash.

Okay, I have a multimeter and was going to check after work. Any idea what the voltage should be while the car isn't running?

I have read all sorts of ranges from 11.2 being dead to below 12 being dead.

Really sounds like a loose connection or bad ground possibly. Have you cleaned your battery connections using a wire brush or sandpaper? Also, there are a number of ground points on that car, including one under the battery tray. I'd check, clean, tighten all that you can find. Then see if the battery will charge using a regular battery charger, then try to start it again. A number of auto parts stores will do a free starting / charging check for you.

Put a voltmeter on the battery terminals and hit the starter. If (when it chatters) the voltage drops below about 10V the battery is dead. If it DOESN'T drop materially then you have bad grounds or a bad connection to the starter; on these cars it's usually the grounds.

ffemtp said:

Really sounds like a loose connection or bad ground possibly. Have you cleaned your battery connections using a wire brush or sandpaper? Also, there are a number of ground points on that car, including one under the battery tray. I'd check, clean, tighten all that you can find. Then see if the battery will charge using a regular battery charger, then try to start it again. A number of auto parts stores will do a free starting / charging check for you.

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Thank you!

So the plan is to check the terminals once I get back as well as clean the ground underneath the battery tray. Then once it is all back in and tightened down, I will then try and jump the car to make sure the car is electrically sound then charge the battery to full and monitor to see if it holds its charge.

Genesis said:

Put a voltmeter on the battery terminals and hit the starter. If (when it chatters) the voltage drops below about 10V the battery is dead. If it DOESN'T drop materially then you have bad grounds or a bad connection to the starter; on these cars it's usually the grounds.

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Okay, will do. I noticed that unlike most cars that tick a number of times when the battery is dead, mine will tick ONE time and then everything inside the car (dash lights, radio, door lock lights, etc.) is completely dead.

That's almost-always a bad electrical connection instead of a dead battery -- and likely, on these cars, on the ground side.

Genesis said:

Put a voltmeter on the battery terminals and hit the starter. If (when it chatters) the voltage drops below about 10V the battery is dead. If it DOESN'T drop materially then you have bad grounds or a bad connection to the starter; on these cars it's usually the grounds.

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The 'chatter' could also be a bad connection.
There's enough power to engage the starter then it drops to not enough power and when the solenoid kicks out it starts the cycle over again.

This weekend at the repair shop I help p/t had a diesel truck they put a motor in that had a intermittent no start / no crank problem.
The battery ground cables were changed at some point and just bolted to the dirty chasse.
Also the starter had a similar ground to the dirty chasse.
I used a Fluke meter with the hi/low record and I recorded almost 5 volts drop from the negative post of the battery to the case of the starter.
The solenoid also had a crack near the positive terminal.
After that the 3 year old 'Autocraft' batteries were bad after charging.

kermit_volkswagen said:

Okay, I have a multimeter and was going to check after work. Any idea what the voltage should be while the car isn't running?

I have read all sorts of ranges from 11.2 being dead to below 12 being dead.

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After the car is shut off for a while I would like to see 12.6 volts.
With age that number drops.
If the voltage drops below 9.6 (iIrc) while cranking the ECU will stop working.

I have another brand new battery in my 2002 Jetta that I could swap to see if it is in fact a dead battery, otherwise a bad connection would probably be it.

Or use science.

With the multimeter connected at the battery posts:

1) should see 12.5V or so, engine off. If not, charge the battery overnight or with some booster cables connected to a running car for 30-60 minutes.
2) when starting the car, voltage should not drop below 10 V or so. If it does, remove the battery and get it tested, disconnect, sand, and clean all battery clamps, grounds at transmission and under battery box (battery is already out!)
3) with the engine running, should see at least 13.5V or so. If not, remove the serp belt and check the alternator pulley clutch. If that's fine, and since there no easy way to tell with a multimeter if low charging voltage is the alternator or the built-in regulator, remove the alternator and get it tested.

All of the above voltages say "or so" because cheap multimeters vary a bit, as do battery voltages, depending on the battery's temperature.

Alright, you've convinced me. As they say, knowledge is power and power is burnouts.

I will be sure and update as to what exactly was going on once these tests are performed. Thanks again and let me know if any more ideas pop up!

Yes, science. Your title says it all. Just troubleshoot one component at a time.

So, immediately found that the negative cable was loose but still securely on the battery. I removed the battery and cleaned the ground just for safe measure and reconnected the battery. I then checked the battery voltage (off it registered 12.5, while running it registered 14.3). I jumped the car as the battery still seemed weak and let it run for awhile. I trickled charged it overnight and this morning it started right up.

I think I will still go have the battery load tested as well as the alternator just for good measure.

Thank you all for the help!

kermit_volkswagen said:

So, immediately found that the negative cable was loose but still securely on the battery.........................!

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That's all it takes, you're done!
If it's been that way a long time, could have overworked the alternator, but unlikely.

kermit_volkswagen said:

I think I will still go have the battery load tested as well as the alternator just for good measure.

Thank you all for the help!

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If its a battery from Wally World (AKA Walmart) I wouldn't doubt its bad after 1 year.
I bought 1 for my Ranger once.
Didn't make it much past the year and out of warranty.
Also make sure you get the correct battery for a diesel, not a gas car.

Many folks buy batteries @ Walmart with good results. You must get the correct size.
The dealership is actually a good source for TDI batteries.

There are only a handful of actual battery manufacturers; WalMart simply has their label put on them. They're no better or worse than anyone else's.

Two batteries ago the dealer beat Wally's price for the Jetta by ~$10 or so, and thus they got the biz. Last time Wally was cheaper was $30, so they got the biz. Just buy the correct size.

As for "best life" (1) use the car; a sitting vehicle discharges the battery, and lead-acid starting batteries DO NOT like being discharged more than ~20% -- ever, (2) CHECK THE WATER LEVEL and when low fill ONLY with distilled water. ALL non-sealed (e.g. AGM) batteries consume some water under normal operation and low water level will destroy a battery faster than anything other than deep discharges on starting batteries (which can kill 20% of capacity OR MORE with just ONE event.)

wonneber said:

If its a battery from Wally World (AKA Walmart) I wouldn't doubt its bad after 1 year.
I bought 1 for my Ranger once.
Didn't make it much past the year and out of warranty.
Also make sure you get the correct battery for a diesel, not a gas car.

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I liked when they were Energizers, not sure about the new one they have. Had an energizer in my mkii and then for 6 years in my mkiv.

In Florida you can expect to buy a battery every ~4 years or so, and you'll find out when the reserve capacity goes to crap on you or you take a trip up north and the car won't start on the 20F morning!

The heat deteriorates them quite quickly.....