CEL on after replacing battery

Maintenance/Repairs
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21

[quote=“db4690, post:18, topic:99785, full:true”]
A word of caution . . .

If you’re contemplating doing your own battery replacements again, you might want to consider a memory saver

Not only will it preserve your radio and clock settings, it will also preserve your readiness monitors . . . an important detail, if the car will be due for smog inspection soon. It would suck to show up at the smog inspection place, only to get turned away, because the car’s not ready. That’s time wasted, in which you could be be doing better things
[/quote]In relatively new cars, I thought these were stored in nonvolatile memory so disconnecting the battery wouldn’t erase them. This is also why disconnecting the battery won’t clear error codes.

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That is incorrect

Removing the battery WILL clear your readiness monitors, no doubt about it

As for the radio and clock settings, it depends on the car, but most cars will need the clock reprogrammed. Some cars don’t require a radio code, but that could be a lengthy discussion, as to the reasons why

As far as “relatively new cars” . . . what is your definition of relatively new?

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[quote=“db4690, post:22, topic:99785, full:true”]
That is incorrect

Removing the battery WILL clear your readiness monitors, no doubt about it

As for the radio and clock settings, it depends on the car, but most cars will need the clock reprogrammed. Some cars don’t require a radio code, but that could be a lengthy discussion, as to the reasons why

As far as “relatively new cars” . . . what is your definition of relatively new?
[/quote]A decade or so old.

To clarify my earlier reply, I was only referring to readiness monitors. My thinking was hat since error codes can’t be erased by disconnecting the battery, readiness monitors should also be unaffected. But I stand (sit?) corrected.

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There are a couple of guys at work that replace batteries, then give me the vehicle to smog

A few times, they have been disappointed, because the vehicles aren’t “ready” when I get them

So they spend time driving them, to get them ready again, and they could have avoided it, if they’d used a memory saver

25

Sure we hired a new mechanic, and my old bud is like gees got to teach them everything. 10 year old knowledge ,is now obsolete. So me a computer guy working with the mechanic guy, to get analysis programs and even just proprietary manuals to work. We are both old school guys making our way bravely into the whole new worlds