I have a 2007 Prius Touring with 296,000 miles on it. I just replaced the battery a few weeks ago with a non-Prius battery. Power and operation were fine, but every time I turned the vehicle back on, I had to disconnect and reconnect the negative cable several times in order to get the dash lights to come on. I replaced it with the correct 12V battery (new from Autozone) two days ago. I still have to disconnect and reconnect the battery cables just in order to get the dash lights to come on and sometimes it will not start, as the light in power button to turn on the car is orange. It will take several attempts at this before the car will start. After just a few seconds, all the dash lights (red triangle, VSC, ABS, etc) come on. Read the codes at Autozone yesterday and the only error code was P0420, which I knew already. I'm pretty sure the cat is not causing this problem. It drives fine, but want to make sure it is safe and also want cruise control. I took it to the dealer a couple hours ago. They said to bring it back on Monday, but the guy told me it is definitely an ABS issue. I did have the rear brakes done a few weeks ago and just replaced the front pads myself last weekend. It doesn't make sense that it is related to the ABS. It also drives fine (except I have no cruise control. It seems like an electrical issue. Anyone else experience this? Thank you.
i can't say for sure, but it might be a failsafe, and when you disconnect the negative, you reset the code, allowing it to start until the code sets again, and you try to start it again
This is the classic failed combination meter (CM) scenario. The installation of your new 12 V battery is now driving the CM electronics at the proper full voltage and has tipped the failing capacitors over the edge. The pinned thread a the top of the Gen 2 Prius Care, Maintenance and Troubleshooting forum, Combination Meter Repair - DIY, has useful info about the problem and how to fix it as well as info about getting an exchange repaired board from Texas Hybrid Batteries.
Thank you. I will take a look at it. Will that also cause the car to not start at certain times? Would it be worth getting one from the wrecking yard?
I wouldn't. For two reasons, 1) the odometer will not be correct and 2) the capacitors will be just as old and you would be advised to change them in any case before reinstalling so you won't be ahead. It would be better to repair your own board (or have an electronics repair service do it for you). You will want to upgrade the capacitors to the higher-rated 220 µF capacitors. This would be the cheapest option. The next cheapest option would be an exchange unit from Texas Hybrid Batteries as linked above by bisco. I hope that helps.
This happens on both my 08 Prii I sent them both in to Texas Hybrid Batteries and he took care of it. Wonderful service and huge peace of mind. Well worth it.
