Hello! I just bought a used 2008 Prius (my first hybrid), so this is my first attempt at using this website. Thank you to everyone who knows more about your Prius than I do. I had my Prius inspected after buying it, and the error code C1378 appeared, which I have discerned refers to the Skid Control ECU. There is apparently a recall for this part in 2010-2014 models, however as a 2008 I don't think I apply. I understand it's a really expensive fix ($2k), so I'm trying to figure out ways not to pay for a new one. I have a drive train warranty with the dealer I bought from, is there any way that this issue would be covered under that warranty? Again, this may be a stupid question, but since I'm new to hybrids I'm still figuring out what parts are connects to each other. If not, I've read that an incorrect C1378 error code can occur if the voltage on the smaller 12v battery is down. Can anyone support this? Are there any other Prius issues that anyone is aware of that can result in a false error code reading? Thanks so much for any and all help.
congrats and welcome! it's always worth checking you 12v health when the prius shows signs of a problem. it's easy to eliminate. take a voltage test in the morning before starting and driving the car. should be 12.4 or better. why not ask the dealer if it's covered? if it does turn out to be the edu, you can probably grab a salvage on the cheap.
DTC C1378 points to a problem with the skid control ECU, the brake power supply which is located next to the 12V battery in the hatch area, or the wiring harness connecting the two. Are you aware of an accident which impacted the right hatch area? To save repair costs you can certainly buy a used skid control ECU but it is very difficult to install because most of the dashboard and steering column must be removed for access. It would not hurt to measure the voltage of your 12V battery and replace it if the open-circuit voltage is below 12.4V - or try charging the battery. I doubt that your dealer would cover this repair under a drivetrain warranty. Usually that is limited to the engine and transaxle.
Thank you Patrick Wong and Brisco for your input! I had my 12v battery checked, and it's running smooth at about 12.2v so that's not the issue. According to carfax and structural inspection of the car, it hasn't been in any accidents, although the bumpers have both been repainted. Pretty common practice with used car dealerships as I understand it, but could indicate a little bumper scratch in the past. But again, no structural damage/reported accidents. I ended up finding a salvaged ECU on ebay for about $40 and my garage said they'd install it for just under $200, so that will probably be my best bet. I'm still waiting on my dealership to see if they'll cover the ECU out of the goodness of their hearts (and the fact that they should have checked the damn hybrid system before they sold it), but not holding my breath. Again, thank you both for your help!
Actually that voltage is quite low so I recommend you use a battery charger to charge the 12V battery overnight. A fully-charged AGM battery will show voltage of ~13.0V.
OH, perhaps I read it wrong. Honestly, my mechanic checked the voltage and said that it was running strong, and I saw the voltage # upside down and thought that is said 12.2v, but I will definitely check with him on what it read at. If it should be running closer to 13v then I will certainly get a battery charger, thank you. I assume they're not too expensive?
To save repair costs you can certainly buy a used skid control ECU but it is very difficult to install because most of the dashboard and steering column must be removed for access. I have replaced many Skid control ECUs. It is a little tight and a PITA first time but it is not necessary to remove dash or steering column. You just need an extension and a deep 10mm swivel socket. A flashlight helps also. fist time takes about an hour....second time about 15 minutes. also........you can unplug all four connectors on the old skid control ECU and plug in the new one just to test without removing the old one.
