A couple months ago, my first gen prius started jerking while accelerating, after i pulled over it wouldn't start and the red triangle of death came on. I left my car sitting in my driveway for a couple months, the battery was completely dead/bad so I replaced it. I also cleaned the MAF sensor. I ran the codes and got P3030 and P3120. From what I've read on here those can be tied to expensive repairs. wondering if anyone has any insight if its worth putting money/time into fixing this or if its time to say goodbye.
You need it capable scanner to get the sub code a three digit numerical code for the 3120. Theother look in hybrid battery for damaged wiring . If imagine with this code a very original or very old battery
P3030 is the wonderfully-named "Battery Voltage Detective Line Snapped". The battery computer has a wire to every other module to measure voltage. They are skinny wires - they don't participate in the main output of the battery. Sometimes this means you need a 20 cent ring terminal crimped on to one of the wires inside the battery. You can probably find out which one's broken if you're willing to disassemble the battery and look. Techstream can narrow it down; it normally shows you the voltage of every two modules, but if it can't read a couple of modules, that tells you which wire is broken. You still have to disassemble the battery to fix it, though. P3120 can be a number of things inside the transaxle, including temperature sensors, resolvers (the thing that decides what angle something is at), and others. Techstream can give you the exact code that tells you what is wrong. For some of the sub-codes, it *can* be a problem in the wiring harness between the transaxle and the hybrid vehicle ECU (on the passenger front floorboard). If you have a code like that, it's probably worth inspecting the wiring harness as far as you can - mice chewing on it, etc. You may notice that Techstream keeps coming up. It is the Toyota diagnostic software for a Gen1. To use it, you need to buy an "MVCI" cable (about $30-$60 for a Chinese one) - the cable usually comes with a copy of Techstream. You will also need a Windows laptop or PC to run it on. Torque, Torque Pro, and Dr. Prius are not Techstream.
