Warning lights are going crazy?

APRILBALL

MEMBER
2017 HONDA CRV
66,000 MILES

I started having issues with my battery being dead and needing to give it a jump from time to time. I knew I needed to have it tested and probably replaced. Yesterday afternoon when I started it, the dashboard warnings and alerts were on, and it was cycling through every message/warning that the car has. I was able to drive it just fine. Last night, not wanting to take chances, I replaced the battery. After installing the battery that car started just fine, but the alerts and messages were still cycling through. I hoped in and drove it down the road a bit and everything seemed to reset. No more messages, lights, dinging, etc. This morning, I started her up and we're right back to the flashing and cycling through all of the messages.
Help!

Friday, January 17th, 2025 AT 1:04 PM

3 Replies

STEVE W.

MECHANIC
14,084 POSTS

The lights coming on after a battery change is normal. They should reset after a short drive. It sounds like that is working but once the key is turned off it resets like the battery was disconnected again. I suspect that one of the fuses may have failed that provides power to the ECU when the key is turned off. That means that the system relearns everything once you drive it, but then "forgets" when you shut the truck off. Very possible that it happened during one of the jump starts and that triggered the first event that made you change the battery. The fastest way to discover if this is the case would be to run through the fuses with a test light. Just buy a cheap incandescent one like the image from a parts store or a harbor freight store. Then go over the fuses in the box under the hood and the one under the dash. Because it does this when the key is off, leave the key off when testing. Connect the clip to a ground and verify it works by touching the battery positive. Now work through the fuses. Touch both sides of the fuses, what you are looking for is one that lights up on one side, but not the other. Replace that and go for a drive. Then see if the re-learn holds after you shut off the key. If it does then it was only the fuse, if it doesn't it could be a problem internal to the ECU. Let us know what you find.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

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