My wife was concerned with the triangle of death when my HV died. I picked up the car and limped on home. The battery is repaired now, but am getting weird codes (C1378 and C1310). I will check the voltage in the am, but is it possible I put a drain on the 12 volt which is unrestorable? It was about 20 miles and 45 minutes on a 5 year old battery. Thanks again, Dan.
no. if the car started, you didn't drain the 12v. it may have something to do with your repair. is the car running okay? what issues are you having?
I don’t understand the post. The HV battery is the one that drives the car. The 12 volt battery runs the computers and lights. What exactly did you do? A Prius does not work like a car with an alternator, it does not even have one. The 12v is recharged from the HV battery. The HV battery starts the engine not the 12v.
Your 5 year old 12v battery is probably on its last leg. See what it reads. Probably needs to be replaced, but not because you limped home. That had nothing to do with the 12v.
the car is running okay now, just these two codes (1310 and 1378). Also the HV battery went down to 2 bars once. I checked the 12 volt cold in the morning and got a good 12.4 volts. Then I unplugged it for a few hours and reconnected it. Next step is to check the torque on the terminal nuts. Any other suggestions why I may get these codes before and after repairing the HV? Thanks for the response, 12.4 in the am, might be ok until I get the c1310 and c1378 codes sorted out. So when the HV dies and the car is limping, does the 12volt take over? If so does it damage the 12v by driving in "limp mode"? Thanks, Dan.
if the hv dies, the car will not move, so, we're not sure what you mean by limp mode. the triangle of death does not mean the battery is dead. it can mean the battery is unhealthy and needs work or replacement eventually, but it may still start the engine and help propel it. when the car runs out of gas, the hv will continue to propel it, but not very far, depending on the level of charge. the 12v is not involved or drained in any way. 12.4 is okay, but on the verge of needing charging or replacement. 2 bars is not abnormal, one bar is.
look up the codes. if you are going to diy, see the service manual for troubleshooting them. it may have something to do with the braking power source on top of the 12 volt.
Those c codes are nags concerning the brakes the c1378 is complaining about the brake power backup supply which is the box just to the left of the 12 volt battery. That box has capacitors that provide emergency power to the brakes in the event the 12 volt dies. It is a 12 volt battery back up box. It has probably become disconnected when the hybrid battery got pulled out. 12 volt battery’s only job really is to close relays when you push the start button and provide power to all the stand by circuits when car is off. Has nothing to do with the hybrid battery. Easy test for 12 volt battery With car off measure voltage at front jump points. Write that voltage down. With car off turn on headlights in high beam. Leave lights on for 5 mins. Then Turn off headlights. With car still off measure voltage at jump points again. See if the voltage has dropped with that load on it. Should not have dipped at all. All 3 of my cars show no dipping at all after 5 mins. Be aware that with all the hybrid battery repair etc the doors have been left open and door lights left on quite a bit draining the 12 volt battery. That will not help an older borderline battery. Replace the 12 volt battery.
Thanks for the response, what I meant by limp mode was very little power but the car moved enough to get home on ICE, not HV, had plenty of gas. Sounding more like I need a new 12 volt, 5 years is a good run. Thanks I'll try that That would be me. Replaced 1 module at 6.6v and put it all back. $1600 for and 12 year old 210k car was hard to justify without trying to fix it myself first. Perhaps it was a mistake, but I have always taken pride in fixing my own stuff. I am not a mechanic, but want to maintain my self reliance, even with a hybrid car 12.4 to 12.0 after 5 minutes, ordering a new battery
read up on the battery rebuilding threads. doing it properly takes time and patience, but will be worth the effort.
