I'm trying to do some troubleshooting on my 2012 Prius today. I'm having some issues getting the green LED in the PTS button to come on for starting. For sure it has something to do with brake pedal switch. I have tried to adjust it, and sometimes it works fine, other times it doesn't. I probably just need to replace it, but Id like to know a couple of things first. 1. Looking at the plug on it, all the wires going too it are very thin and tiny. Id need to look again, but I think there is a small blue one, a white one, a red one, and a few others. 2. I traced the blue one to the 10 pin connector at the drivers kick panel plug. It shows 12 volts when I press the break and zero when I let go. 3. Do all the other wires from the brake switch plug end up going here as well? 4. Do you know which of these are related to "PTS Green start" and what they should read when the break is pressed? Id like to confirm with my meter if the car is not seeing what it wants before I go thru the trouble of replacing this. Dealer wants $200 parts and labour.
RED PURPLE GREEN BLUE BLACK I figure one brings power, blue shows that power when the pedal is pushed. Maybe another is for the cruse-control? Maybe another is for the PTS/put in gear? And maybe another for the break lights? Anyone know for sure?
me neither, wouldn't think so, unless the other end of the wiring was involved, or it is not the switch at all, and something near the accident repair
I have had that stereo in there for a long time, reciently just solved the battery charging issue. I dont think its related. I was mistaken about the wires, there are only 4. Black Red Blue and Gray. Pretty sure I know what the blue one is, but no clue on the others or where they even go or what they do.
How exactly did you solve the charging issue ? And why do you think it is not related ?? By far, the most common cause of intermittent no start is 12 V battery problems.
The charging problem was solved in a crazy convoluted way that is way out-of-the-box for normal car audio 12-volt work. It involves a time delay relay, "disconnecting" the car battery completely from the car and from the stereo. At that point, both the car and stereo are running 100% off the internal car's inverter. Also, the car's 12volt power running an external inverter, that runs a battery charger, and that charges the "disconnected" car battery while the car's on. Im sure this is putting a very heavy load on the car's internal inverter, but my battery charger sees mostly a "nearly fully charged battery". So the battery charger doesn't really have to work very hard, which makes the external 120v inverter not work much harder than it already was working to power the AC parts of the car stereo system. (a home theatre AVR). I have noticed a small loss in MPG, due to the extra load on the 200 volt battery having to keep the car's inverter happy running all my junk. This was my last ditch effort to avoid having to plug in my prius's 12 volt battery, and so far, week 2 in cold weather, its working perfectly. When Im having trouble starting my car, the PTS wont turn green when I press the break, but if I nuts on the break, pumping it wildly, that problem is solved for a few days till next time.
WOW. All that for a little audio. I think you are doing yourself a dis-service if you consider ONLY the brake switch in this convoluted setup. Given what you have described, my prediction is that this is only the first of several strange and "unexplainable" problems that will crop up. Good luck.
Maybe, but I can tell you remote start work EVERY time, and after the car is running there are zero indications of any issues at all, no dimming lights, no dash errors, everything works fine, with the audio stuff on. Side question on the same topic: Does anyone know for sure if the Brake Stroke Sensor (the other unit wired to the brake) has any bearing on the PTS button to start the car, or is that purely a function of the brake light switch like I think it is?
UPDATE: I found the issue. The actual brake light switch had a cracked holder which keeps it in the right place to pop open when you press down on the break. Not sure how this happened, but I was able to get a used oneat a junkyard, and all is well now.
