Can a Bad Battery Cause Electrical Issues?

[Donald]

Originally Posted By: Nick1994
Dealer batteries are highly recommended for the TDIs because of the power it takes to start them.


A dealer and an aftermarket battery that are both the CCA as listed in the owners manual will start the vehicle equally well. Thats of course if both are in good shape.

There maybe some sleazy battery companies that overrate the CCA, but that should not be the case for a quality brand battery.

 

[zzyzzx]

Originally Posted By: rjundi
Power window "lose" its programming so it would not longer go down. Had to look up reprogam.


??? Somebody took a perfectly good working power window setup and decided to add a computer to it, just because they could???

 

[Rand]

Listening to the radio for 30min at a time can cause deeper discharge of the battery.. and depth of discharge is directly related to battery life. Could be a contributing factor to lasting 2 years.

The stock battery is 640CCA.


I'm showing 730, 760 and larger available.

 

[SHOZ]

Originally Posted By: zzyzzx
Originally Posted By: rjundi
Power window "lose" its programming so it would not longer go down. Had to look up reprogam.


??? Somebody took a perfectly good working power window setup and decided to add a computer to it, just because they could???


They do that for the auto drop when opening the door on frame less doors or for the safety stop when an object is in the opening and trying to close the window.

 

[Nick1994]

Well it wouldn't start this morning, it cranked one time and that was it. Going to get a new battery this afternoon and will check with the TDI forums which battery they recommend. Definitely not the easiest battery to change. Thanks guys

 

[The_Jeff]

I had a 94 saturn with a conked battery. Wouldn't crank so I roll started it... stick shift.

It ran, but the ABS light came on, because something in the crank-boot-up sequence was FUBAR.

I suspect you have a momentary loss of voltage while cranking that's messing your stuff up.

But, like I said above, on a diesel that's inexcusable. They must be using gas-engine body control modules etc that really need to stay above an arbitrary voltage, like 10.5 or so.

 

[Gokhan]

Weak batteries will cause slow cranks, no cranks but just clicks, no sound at all, and even stalls while driving.

When you get the new battery, avoid unnecessary drains or deep drains and top off the electrolyte with distilled water regularly. Car shouldn't be parked more than a few days.

 

[Nick1994]

I just called the dealer and they said to bring it in and if it fails on their tester then I get a free replacement. Score! Hopefully this goes well.

 

[Gokhan]

I had a new Toyota that wasn't driven frequently and the battery failed in a year. I got a free replacement. The replacement OEM battery seemed higher-quality than the factory OEM. The car was always garaged. It's crucial for battery health that the car is driven regularly and unnecessary drains are avoided.

I shake my head when I see most luxury cars don't turn off their lights for a while when they are parked.

 

[Vikas]

On your car the only thing cheaper than the battery is filling the diesel tank; so yes, that would be the first thing to try.

 

[HangFire]

Originally Posted By: Gokhan
It's crucial for battery health that the car is driven regularly and unnecessary drains are avoided.

I hear what you're saying, but periodic recharges will also keep a stored battery in good health.
Originally Posted By: Rand
Listening to the radio for 30min at a time can cause deeper discharge of the battery.. and depth of discharge is directly related to battery life. Could be a contributing factor to lasting 2 years.

The stock battery is 640CCA.

I'm showing 730, 760 and larger available.

While a higher CCA rating usually goes hand in hand with a higher Reserve Capacity, it is the RC rating that you should be looking at here. The RC can and does vary a bit from model to model even if CCA is equivalent.
Originally Posted By: zzyzzx
Originally Posted By: rjundi
Power window "lose" its programming so it would not longer go down. Had to look up reprogam.


??? Somebody took a perfectly good working power window setup and decided to add a computer to it, just because they could???

Yes, that would be Acura, the Honda Pilot too. Fortunately reprogramming is trivial and the procedure is in the owner's manual.

 

[Nick1994]

Wow! I used a volt meter and it was at 12.3 volts and wouldn't crank it. I jumped it with the 70' Beetle and it took a LOT to get it to start. Lots of slow cranking that just can't get it fired. Finally did and voltage was about 14.4-14.5 volts. Then I noticed on the drive the the dealer the tach wasn't working, but everything else was. We'll see what happens.

 

[Gokhan]

Originally Posted By: Nick1994
Wow! I used a volt meter and it was at 12.3 volts and wouldn't crank it. I jumped it with the 70' Beetle and it took a LOT to get it to start. Lots of slow cranking that just can't get it fired. Finally did and voltage was about 14.4-14.5 volts. Then I noticed on the drive the the dealer the tach wasn't working, but everything else was. We'll see what happens.

14.3 V that you saw is not the battery voltage. It's the alternator voltage, which is controlled by the integrated-circuit voltage regulator on the alternator.

Battery voltage needs to be measured in an "open circuit," meaning that you need to disconnect the negative terminal of the battery before you measure the battery voltage. This is the so-called "open-circuit voltage." Open-circuit voltage for a fully charged battery should be 12.5 - 12.7 V, depending on the temperature.

http://en.wikipedia.org/wiki/Automotive_battery#Terminal_voltage

Also, even if the open-circuit voltage is good, if the battery is unhealthy, the "internal resistance" of the battery could be so large that the battery won't put out much current. The {closed-circuit voltage} of the battery is the {open-circuit voltage} minus the {internal resistance multiplied by the current drawn from the battery}. For example during cranking, a large current will be drawn by the starter and the closed-circuit voltage will be much smaller than 12 V due to the internal resistance of the battery.

 

[Nick1994]

Originally Posted By: Gokhan
Originally Posted By: Nick1994
Wow! I used a volt meter and it was at 12.3 volts and wouldn't crank it. I jumped it with the 70' Beetle and it took a LOT to get it to start. Lots of slow cranking that just can't get it fired. Finally did and voltage was about 14.4-14.5 volts. Then I noticed on the drive the the dealer the tach wasn't working, but everything else was. We'll see what happens.

14.3 V that you saw is not the battery voltage. It's the alternator voltage, which is controlled by the integrated-circuit voltage regulator on the alternator.

Battery voltage needs to be measured in an "open circuit," meaning that you need to disconnect the negative terminal of the battery before you measure the battery voltage. This is the so-called "open-circuit voltage." Open-circuit voltage for a fully charged battery should be 12.5 - 12.7 V, depending on the temperature.

http://en.wikipedia.org/wiki/Automotive_battery#Terminal_voltage

Also, even if the open-circuit voltage is good, if the battery is unhealthy, the "internal resistance" of the battery could be so large that the battery won't put out much current. The {closed-circuit voltage} of the battery is the {open-circuit voltage} minus the {internal resistance multiplied by the current drawn from the battery}. For example during cranking, a large current will be drawn by the starter and the closed-circuit voltage will be much smaller than 12 V due to the internal resistance of the battery.
I know it's not the battery's actual voltage while its running. I posted that to show the alternator is working properly. I checked it before I hooked it up to the jumper cables while it sat all day and that was the 12.3 volts.

 

[CBR.worm]

I've got two cars from different MFG's that act crazy when the battery is low. In both cases the battery will have enough juice to start the car, just cranking slower than normal. One will have a high, lopey idle and random warning lights. Might be ABS, or VDC, or AT or AWD, etc.

The other has random systems (I-drive, wipers, AC) that don't work and will have a service indicator set.

 

[Nick1994]

Well I got the new battery. It really cranks fast now! The tach started working but the airbag light is still on. Oh well I'll figure out the electrical gremlins some day. Last time the airbag light was on it was a seatbelt sensor.

 

[Gokhan]

You may want to monitor your battery voltage for a few weeks to make sure your charging system is healthy. It needs to stay around 12.6 V, without dropping over the course.

 

[DoubleWasp]

Originally Posted By: Miller88
I had a battery go bad in my Cherokee. Voltage wasn't that low (somewhere around 11). It would crank and crank and crank before starting. When it did start, it wouldn't idle.

Cranked at it's normal (slow) speed.

I was going to replace the crankshaft sensor, played around with some other stuff. It was suggested to change the battery and ... it fixed it.


11 volts is as far off the map as Guam. Anything less than 12.5 and you really need to start worrying.

OP: Yes, a bad battery will cause electrical issues. In our Rams, it can cause them to light up like a Christmas tree with errors.

 

[2cool]

Originally Posted By: geeman789
Sure, it might be the battery, heat kills batteries fast... but, once running, the battery is not powering the electrical system, the alternator is. Seems strange that the glitches would occur while driving. And listening to the radio does drain the battery, especially if the key is in the run position vs acc. position... been there, done that, needed a boost... and a new battery shortly after.

Or, maybe the notorious VW electrical gremlins are showing their smiling faces ...

But start with cheap stuff first...

Agree to start with the cheap stuff, such as cleaning terminals. Before you do, get a Keep Alive Memory to save your pre-sets.
One of the functions of a battery is to act as a voltage load leveler for charging system output. If the battery is partially sulfated, i.e. can't absorb the incoming current as it arrives from the AC generator, fluctuating voltage now reaches the electrical harness. As a result, fluctuating voltage CAN cause electronics to go "buggy".
Nobody makes a battery that will withstand heat for more than 3 years; it's feasible but would be prohibitively expensive. One common mistake is to forget to re-install insulating jackets or battery cooling boxes as from the factory.

 

[supton]

Aibag light likely will not go out by itself.

I wonder if you really need a "good" TDi battery down there. Too warm to need the cold cranking amps. A good battery yes but like what i need for sub zero?

I would pull the battery, I want to say there are some problem grounds under it. Hard to believe you of all people would have corrosion issues, but perhaps the battery boiled over at some point and has lunched some wires.