Hi all, I had scoured around in search and found some interesting information but still no specific direction and was wondering if anyone has a solution that may help out. So, purchased the Prius with 111k - I know 2nd day, was adjusting new headlight bulb with lights on shined against garage backdrop and noticed headlights fading until finally out. No interior lights on, knew the battery was probably done. It was a Toyota brand battery, autozone charged battery and noted it was dead even after full charge. I ended ip dropping a new battery (optima) and the battery issue appeared to be gone. A week later, I was leaving a parking lot and noticed the dash combination meter did not display anything, the MFR? Display was on but did not display mileage or anything. I still drove, got home and the engine would not shut off. Hit the power switch for about 10 seconds, and the car did shut off, MFR remained on, back hatch door would not open. I hit the passenger unlock button (just because I was on that side anyway) a few times to unlock and out of nowhere the dash lit up and everything worked like before. Fast forward a few days later, did the same thing but not as bad, went home and parked. Had no issues but I do see that my time clock is off a few hours, and mileage tracked on MFR resets....this is with the combo meter working okayI or displaying. So, from what I read, should I just take the dash apart and test the voltage on the capictor thingies - see if they are going out and replace as necessary? Is there anything else I could do to help diagnose this...the help and response have been amazing from this forum. Thanks in advance
@Texas Hybrid Batteries repairs combo meters. Texas Prius Battery Replacement They also have a page with a form where you can ask any questions. This seems to be a good, inexpensive option.
Make sure all your 12V battery connections are tight. Check both terminals and also check where the ground wire connects to the body that it's tight and clean. Combo meter would be the next thing to check, but I don't think it will cause all the stuff you're seeing. If it is the combo meter, @Prodigyplace listed a great source.
Do 2nd gens only have one 12 volt battery, in the rear is only place I've replaced. I will do a once over and make sure nothing came loose, thanks for the advice.
Yup. Gen 2 & 3 are under the deck by the right side tail light. Gen 4 is under the hood. Not sure about Gen 1. It's pretty common to not get the terminals tight when replacing a 12V battery. But that ground connection can get corroded as well, although that's probably less likely in AZ unless you're in the mountains and they salt the roads.
I think some people have needed to check where the negative battery cable connects to the chassis too. It can come loose.
Exactly. That's what I meant by the possibly corroded ground connection. I should have made that more clear. Thanks.
I guess I needed to translate from electrician-speak". I took electrical classes in high school in Canada. In the higher grades we were a class of seven guys when a Christian teacher. He arranged for us to plan & wire a new dining hall building for a Christian youth camp. I remember working in that building doing the wiring. The building was on a bit of a hill and they had not yet installed windows. That made it quite cold. IIRC the only complaint from the inspector was they initially could not find the weather-head cap for competing the connection on the power pole. Later on, for several years he was a member of my parents' church and he periodically asked how I was doing down here in Virginia.
Okay, just checked, everything seemed pretty tight, negative to bolt in back metal frame was secure. I did notice a white wire hanging by itself, with a metal loop intended for a bolt to pass through. Since it was near and close to negative side - I traced where it was coming from was a bunch of wires zipped tied to rear bottom hatch running along towards the driver side tail light area. I know there was a disconnected red positive wire that I believe is for tow lights on rear, I kept that disconnected. I went ahead and bolted the white wire along with negative to ground frame
You can always tell an electrician, but you can't tell them much. Is there any change, is it intermittent?
I have been an electrician a couple of times in the military myself so I'm not just picking on you my friend.
Not according to Toyota’s Electrical Wiring Diagram, but if aftermarket wiring was added for trailer lighting, I suppose someone might have connected the return there, rather than using one of the other ground points on the car. The Electrical Wiring Diagram shows that most of the wires factory connected at ground points should be white with black stripes, brown, or black.
Not offended a bit. I was sure it was just good humor. In fact, I've been told by people I trust that, if not for my sense of humor, I wouldn't have any sense at all.
So, a quick update - I havent seen the dash light issue since, however, the clock sometimes stops and is delayed when I get back in the car say from work. Also, all preset radio stations reset back to non programmed stations or default. Its as if you were to pull the 12 volt battery out and then reconnect it. All fittings are tight, no corrosion in front terminal area, everything in rear battery area fine - new Optima yellowtop.
Sure sounds like some sort of loose connection in the 12V circuit. <need head scratching emoticon here>
I am having something similar happen with my 2008 Prius. About 3 months ago I turned my car on and got a big red triangle saying the battery/electrical system needed to be checked. Brought my car to Pep boys and they replaced the 12v battery. About a month later, had an issue where the dash lights wouldn’t come on (has happened a few times) but then they do come back on usually the next day. Also, a few times the car wouldn’t turn off (found the trick to get it off eventually). Now, the clock keeps resetting and sometimes the door locks don’t work when using the FOB.... went to start my car today and now it won’t turn on. PLEASE HELP!! is it possible that the battery they put in is no good? Or could there be a bad connection? Everything was working fine until the battery was replaced... I don’t have any tools to check the battery voltage etc... Should I just bring it back to pep boys and make them replace the battery again? I finish paying the car in November so I’m thinking it may be time to trade the ol gal in before more issues start popping up... Any advice is appreciated. Thank you!
Welcome to Prius Chat . In hearing your explanation, it sounds to me like it is connection related, as the clock keeps resetting . By some questions: How many miles on your Prius? Has your Prius experienced any accidents? Have you checked the battery connection as well as the ground cable? What is the battery voltage reading? Keep us posted .