I noticed this morning that about 1-2mi into my trip this morning that things didn't seem "right". I noticed that it was feeling sluggish (sort of like I was driving up a hill), but I'm in south GA, there are no hills. I switched my MFD, and noticed that I had 1-2 pips of batter, and was in the purple. I pulled over, turned off, restarted and then eased on up the road. I forced (by driving lightly) to stay in (and I don't know the tech term) charge mode so that all the electric motor power would go to the battery. I drove on to work (65mi) and it seemed ok, even though I didn't stop/start much until the last 5-6 mi. Lunch time. Seemed like the same thing. As long as I babied it, it seemed ok, but I had to take it easy and not accelerate to hard or it would become sluggish. Just seems like the HV battery is having trouble charge, and the ICE is compensating and struggling in the process. So, my question is this at 185K miles on my '09. Do I need to start looking at battery replacement options, or is there another part that I need to look at first? It did this same thing about 6mo ago, the dealer recommended that I replace the 12V battery and I did, and things picked back up then. My thought was to take to autozone or the like and have them check for codes and go from there. BUT I figured the experts on here would know best as how to advise me. Thanks, Brian
Weird stuff happening? MPGs dropping? Test The Battery | PriusChat Let's see if its the 12 volt battery first. Given your mileage, it is possible that its the HV battery. Does the battery meter on the MFD fluctuate from Pink/Purple to Green?
Yeah, defiitely test your 12V battery first. Another thing. Does the charge stay low (like 1 or 2 bars) for a long time, or does it only happen near the beginning (first few minutes) of each journey? If it's only happening at the beginning of each journey then warming the engine for 1 minute can actually help.
I did replace the 12v about 4 months ago.... Think I got a bad one? It gets up to 3/4, but struggled to do that. It hit the green once, but definitely don't stay there long. I will checkout the above post, after work. I only have the phone right now. Thanks, Brian SCH-I535 ?
What warning lights are on? Any messages or warning icons in the MFD? If there are no lights or warnings present, then it is not likely there will be any DTC to retrieve.
definitely check your 12v just in case. that's the easiest place to start. it could be your hv, but you usually get some warning or the charge meter keeps going rom full to empty over and over.
Ok. I got home, put in diagnostic mode and everthing there checked out good per the post linked above (thanks!). So, the 12V battery is good. I will check the vent in the back, but it did it this AM when it was nice and cool out, but I will rule that out as well.. Thanks for all the quick responses, Gotta run get the kids.. I hope... Brian
Brian, Keep a eye on the MFD. If you start seeing mad swings from purple/red to green and back down real fast that is a sign of impending doom on the traction battery. First thing in the morning when car is warming up traction battery is used heavily since the ICE is working hard to heat the cat's up IIRC. It is normal to see the battery drop in the morning if it is getting weak and tired. Bisco suggests letting Prius run for a minute before driving off when cold. Helps to get the battery charged up a little before you start off. Check the vent in the rear seat. Put the Prius in "Ready Mode". Then place a dollar bill over the vent. If the dollar bill does not stay on the vent and falls off, the fan is NOT working properly. If that is the case, the fan either needs to be cleaned or replaced. Best of luck to you, Ron (dorunron)
I will check all of this. The battery has been up and down, never really making it up to green, and yes, in the purple some. Have not, I will check when back at home. Thanks, Brian SCH-I535 ?
Well, I'm sure the 2qts of oil I just put in it didn't hurt the situation. Gonna see how it runs now..... SCH-I535 ?
These cars are known to burn some oil at high mileage. When the reminder light turns on, that means you've already gone 5000 miles. The cars can develop a burn rate about 1qt - 2qt every 5000 miles. Some even more severe than that. Make sure you keep an eye on the oil level and add BEFORE it gets low.
So here is my educated guess at what happened. Oil got low... Engine was fighting to push the car and me down the road at 70mph... AND charge the battery. It knew it had to charge the battery, so it fought to do that, and the "pickup" suffered.. not to mention the lack of lubrication that drug on it. It couldn't do either of the two well, and since the battery wasn't charging well, it kept charging the battery, to no avail. That was why it took FOREVER to get to the green state of charge, and would easily slip into the purple. Sort of like putting on a sweater in June, a backpack of 240lbs, and telling you to run a race, with my hand over your mouth.... Stupid, stupid, stupid.... Thing is, I knew that it burned about 1qt / 3000k miles or so.. I just overlooked that fact. AND I think I underestimated that direct effect that a lack of oil has on the engine.. and that lack was severe. THANK YOU JC91006 for the advice.. it saved my butt, I think. Seems like everything runs good now. I took it out for a trip after dinner.. Seemed to run MUCH better, and the batter seemed to charge as well as normal. Thanks for the quick response of all! Brian
Watch out for an engine oil consumption rate that may now be greater than the rate that you've documented, now that the oil level dropped below the minimum acceptable level. The engine oil capacity is 3.9 quarts and the difference between the upper and lower dimples on the dipstick represents 1.6 quarts. Hence the minimum acceptable oil amount is 2.3 quarts. If you were able to add 2 quarts to bring the oil level to the upper dimple, then the prior oil level was at only 1.9 quarts. If the oil level is now somewhat below the upper dimple then the prior oil level would be correspondingly lower. This means that permanent damage may have occurred to the engine while it was operating with the prior minimal amount of engine oil. This is especially likely since you noticed driveability symptoms such as poor engine power.
No, it's not a lucky guess, it's a PC educated guess. Low oil is associated with bad performance as the engine is starving for lubricant. He thought it was his battery but he said the 12v battery was new and it didn't make sense for it to be the battery again. After reading his comment about the maintenance light on and having 180k miles on the clock, I thought he should check his oil level first.
I'm a little bit doubt that lack of this much oil (0.4 qt) will cause lot more friction internally, that show such dramatic engine performance drop, especially when this happens suddenly. Just my guts feeling.
