I managed to get the 2003 Prius running that was having issues. It is having some misfire issues, but I'll worry about that later. I put the car in D, and it moved forward, but wouldn't really go above 5mph. I put it in R, and uh oh. The square around the R started flashing, check engine light, and the car would not move even at full throttle. The code I read was P3125, Inverter Internal Short. Did some research online, and I found some vehicles had this code and needed an inverter. Others had a problem with the stator in the transmission. The dreaded TRIANGLE ! is also on. Is there a chance it's just the transmission? I have a 2001 so I could do some parts swapping if necessary to troubleshoot.
Ok, we do not have enough information: what subcode? A Prius-aware scanner can report the nearly three dozen subcodes that will help us understand the particular failure. It could be as simple as simple as a loose connector but without the subcodes, it becomes harder. you will find a detailed list of the subcodes and affected systems in Volume 1 of your copy of the NHW11 shop manual. About 20 pages, a little too much to post here. what are the 19 module pair voltages? when the engine runs, does it charge the traction battery? How many amps? Getting the engine to run, even roughly, is a good start. Use your Prius aware scanner to get the rest of the data and follow the good advice in Volume 1 of the 2001-03 Prius shop manual. You'll be OK. Bob Wilson
My actron is good, but shows no subcodes so it will not suit my uses on a prius. Did some searching, is this a good one for my needs: Autoenginuity Windows Eobdiv Eobdv OBD2 Scan Tool Scanner USB | eBay
Its good but read this post for more info. You will need to mod the OBD2 cable. AE Pig-tail and code flasher | PriusChat
Out of that list of problems, there's at least one thing not to worry about. The square around R always flashes. -Chap (Oh, wait. Did you say "square"? Mine has, like, rounded corners. Your combination meter needs replacement. )
I would fix my engine missfire first,it should give you a code of which cylinder it is. After you get the engine running good than I would tackle the p3125 code. Its a whole lot more easy to replace an ignition coil and get the engine running good , "if its the coil"than to deal with a trans. or invertor. Its cheaper too.....just my 2 cents worth.
