I have a2002Toyota Prius. For several years,the car has a problem I can not solve.Suddenly warning display screen appears with blinking "Hybrid System Warning Light". The car moves very slowly: 15 - 20mph.Pressing the gas pedal has almost no effect.Then the car begins to jerk(that is quickly gaining speed, then again goes slowly). I stop the car,stop the engine and restart after 5seconds.The car moves fine without any problems (until the next failure).This happens a few times a week. I have several times appealed to the dealers of the company"Toyota"and paid them for the diagnosis of $150.Here is their code: code P1120, P0300, P0301, P3191, B0101, B0102, B0106, B0107, B0131, B0136, C1521. They had no opinion. They proposed replacing accelerator for $500 maybe it will help.But I cannot pay them for experiments. Maybe someone has had similar problems with the Hybrid System and can give me advice? Thank you for your time. James
A quick breakdown of all your codes,P1120 is accelerator position sensor problem,c1521 is power steering assy problem,your B codes all have to do with your air bag sensors,maybe clock spring??. P 300 and 301 have to do with engine missfire/cyl 1. and the last 1 is the engine is not running when it should be or it died. I would agree with Bob Wilson,sounds like your acc. position sensor. That is where i would start..
I always start by checking the 12V battery. A weak 12V battery can cause all kinds of funkyness. Next; Scan and record codes, clear codes then see which ones come back right away.
You did not make any mention of mileage, however, I would speculate based on the codes seen the most prudent and financially beneficial steps are: 1) Replace sparkplugs (misfire on cylinder 1 on any car is usually indicative of bad plugs, failures on 3 and 4 are usually wiring related, this is just from experience), nevertheless, it does not hurt to put in new one's whether it was the problem or not! This is about $60 in parts and about 30 minutes. 2) Check the MAP sensor, located just under the air filter. Clean it out with throttle body cleaner. A bad MAP sensor will not permit the car to accelerate very well, and in fact will trigger a limp home mode that you are experiencing. Or just buy a new one. Only $78 bucks at Toyota. Two small screws, unplug and put in. About 30 minutes. 3) Check the 12V battery voltage. The Airbag errors and that last error indicate this could be a problem. Might as well replace it anyway as these batteries only last a maximum of 3 years anyway. 1.5 years is a good timeframe. Buy a Toyota battery, or Optima 51R battery or a Odyssey battery they all work fine. Prices and time vary, but should not exceed $200 (in the USA anyway). In Canada, the 12 V from Toyota is no longer available. You can find it online however. 4) Replace accelerator pedal. This is a relatively easy task, and is well documented on PriusChat in the G1 forum. Not cheap, but that would be my last resort. Do not worry about the Airbag codes as those are not a concern in a car this old. They most likely don't work anyway. LOL! Let us know your progress. I am keenly interested.
Here I'm not trying to quibble for its own sake, but to avoid puzzling the parts-counter guy, ask for a MAF sensor. There is such a thing as a MAP sensor and some cars have them, but not a Gen 1 Prius. The Panasonic in my trunk has a date code of 120406. This winter it is just beginning to show voltages low enough that I will start saving up for a replacement, but it hasn't let me down yet. -Chap
