Consequences of Disconnecting Battery

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That list is very broad... I never has issues with our MB and BMWs with battery disconnects. Usually the only things required where: setting date/time, synchronization of windows and roof and completing drive cycle.
This is our experience also, from everything in my sig (well except for the Piper). Record your radio codes!
 
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Displaced Texan in Mexico City
modern vehicles can be a PITA with TOO MANY gadgets + NANNIES so i dont buy them, even DI is a no-no for me!!!
Yea technological advancements suck, like airbags, ABS, stability controls, and crash avoidance. Nevermind that cars today are faster, more efficent, more powerful, safer, and more reliable.
 
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The Noco is 9V and was $20 … so I ordered one from eBay … we will see …
I used one of these when I changed my battery a couple of months ago. It appeared to work. I had used a 12V power supply connected to the battery cables the last time and that seemed to work, too. The only thing I had to reset was the clock (both times), though, I'm not sure why.
 
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Dont trust the OBD port to power the car during battery disconnect. That failed n my lexus

Purchase a charger /maintainer with a maintenance mode designed to simulate a connected battery.
 
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Cold Lake, Alberta, Canada
On my '06 Jetta you might end up with steering that doesn't work properly.

If the battery voltage goes too low or the battery is disconnected the steering needs to re-learn where center is.
You have to turn the wheel to full lock in either direction after disconnecting the battery so it knows where center is. If you don't do that and just drive off it will try to figure it out on its own based on your steering inputs which can lead to things like the car wanting to turn left hard and only one turn of steering lock to the right which is a bit scary (ask me how I know). Why they couldn't install some sort of sensor to tell when the wheels are centered with all their fancy "German engineering" I don't know.
 

gathermewool

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You missed one for Subarus. Disconnecting the battery may result in permanent AWD! I've experienced this personally!
 
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Not the experience with mine. The steering light goes off after a few feet of driving.
Huh, definitely my experience driving mine. '06 TDI. It did it a few times a couple of winters ago when my battery was going bad and it was cold enough to have difficulty starting.
If you're lucky enough that you have to use full steering lock in both directions shortly after leaving your parking spot (or possibly if you leave the vehicle idling with parking centered for long enough?) you wouldn't notice it.
VW forums let me know what the "problem" was when it happened and how to correct it (disconnect the battery, reconnect it, start the car, turn the wheel to full lock in both directions, drive off) so it's definitely a thing. It wouldn't be a big issue if it didn't cause a dangerous condition.
 
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Never had an issue--until we got our CRV. Battery went flat on us. Now the radio is dead, it wants the code, and I can't find it (new to us). Not a huge loss, as the radio wasn't very good (no cassette tapes here, and the six CD changer was broken) but still annoying, as the FM receiver is now dead. Annoying "feature" that I wish didn't exist--thankfully none of my other vehicles had this.
 

JHZR2

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Radio codes and PCM/ECU parameter re-learn is old news, as is the OBD “not ready” code, after having power loss or codes cleared. Nothing new there.

Some of these other things listed sound like faulty engineering, but also somewhat dubious that they universally happen. a bad diode or shorted cell in a battery can easily take the dc voltage lower than computers and other controls will allow. Then what?!? Same thing when swapping a battery. So now you can’t diy it in a parking lot in the rain, because you don’t have a 12v power supply? Not sure how realistic thst is. No doubt these bad consequences have happened, but the other circumstances need to be considered.
 
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Take out the radio and bring it to your dealer's parts department. They should be able to get the code off the serial number on it.
More work than it is worth. It has a cassette deck, which may or may not work, doesn't matter as I don't have any tapes. The 6 CD changer is kaput too. And no Bluetooth. If I yank it, it's not going back in. For now it can stay dead, it's going to a teen driver in the end, one less distraction. :)

Not sure what a dealership would charge to look it up anyhow. I mean, I didn't buy this car from them, so why would they give free support? Maybe it's trivial work them, dunno.

Not sure why Honda did this in 2003. But my '10 and '11 Toyota's don't have this problem. I realize it's discourage theft but it makes my life harder, so I don't like it. Puts me in the minority I know, luddite etc.
 
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More work than it is worth. It has a cassette deck, which may or may not work, doesn't matter as I don't have any tapes. The 6 CD changer is kaput too. And no Bluetooth. If I yank it, it's not going back in. For now it can stay dead, it's going to a teen driver in the end, one less distraction. :)

Not sure what a dealership would charge to look it up anyhow.
About the only time I turn on the radio is to hear the traffic report and weather. It would still be good for that. Dealership shouldn't charge anything. Go in to buy an oil filter or wiper blades, and ask, Could you check the code on this radio while I'm here?
 
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About the only time I turn on the radio is to hear the traffic report and weather. It would still be good for that. Dealership shouldn't charge anything. Go in to buy an oil filter or wiper blades, and ask, Could you check the code on this radio while I'm here?
Not a bad idea. I'll keep that in mind, next time I think of a trip to the city maybe it'll be something to do. I should look to see what wipers this has, probably could use some spares.
 
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