VSC Code 34

I nearly killed my 12v battery this week when I left my dome light on in the Airport parking lot. When I got back to the car I was able to pop the hatchback, but there wasn't enough juice to start her up. I was able to get a booster pack jump and it looked like everything was fine (didn't even lose the radio presets on the aftermarket deck). I had a long ride home to charge the 12v battery up. I changed out to the Optima yellow-top a couple years ago, so I'm not too worried about the battery being crippled. I've gone into the onboard signal menu and the battery voltage is well within spec idle and under load after a few hours of driving recharge.

Low and behold, the next day the VSC warning light came on and won't go off. I am NOT getting the brake (!), red triangle, or ABS warning light as others have received with 12v battery issues. I put on the OBC scanner and pulled no issues. I jumpered pin 13 TC and 4 Gnd on the interface to get the flash codes and sure enough, I'm getting a 34 code on the VSC system. I have been unable to clear the code via tapping the brakes.

Anyone know what a VSC 34 is? Anyone know how to clear it?

 

I should have been more clear. It is just coincidence that I needed to drive, not that I was driving to charge it. I was testing the battery 2 days later after driving well over 200 miles. The car was sitting for 3-4 hours before I tested it and I made sure that I watched it under load (A/C and lights on) for a good 5 minutes to see if the voltage would start plummeting.

 

seilerts,
Thank you for the info on the code. Google wasn't coming up with the what that code meant. I haven't been digging around in the Prius for anything for a long time, so I don't think there is a reason that the wiring and/or sensor would have been disturbed. I don't know where the skid ECU is located, is there an easy way to inspect the wiring path without pulling the center console?

FWD,
I haven't had a chance to pull the battery for 15 min yet, I just don't have the time for the exercise during the week. I've ordered a BatteryMinder that handles the AGM cells since I've been meaning to get one since putting in the Yellow Top Optima. Over the weekend I'll pull the cover, install the quick-connect cordset and let the BatteryMinder work on the battery overnight before reconnecting. I'll report back what happens.

Thank you for the suggestions!

 

Ok, I got the BatteryMinder a day early, so I pulled the covers, disconnected the battery and let the Minder do it's think over night. On the upside it didn't give an indication that the battery was sulphated and all indicators were green all the way. Upon reconnecting the battery, I still have the VSC warning light and now I'm pulling code 34 and 36, but I was able to clear 36.

Is there a way to test the Yaw sensor, or are we down to check the connections and if they're good replace the sensor?

 

Oh, of note, I haven't been able to drive the Prius anywhere as I currently have 2+ feet of snow in the driveway.

 

I went to the junk yard today and pulled the part from an '05 that met it's end via a rear-end swipe. The first one they showed me was a '04 that appeared to meet an immovable object at about 60 MPH. I thought the Yaw sensor would more likely be damaged in that accident. I pulled the ground on the battery, plugged it in and reset the codes and so far I'm code-free on the 30 mile trip home. I hope it stays that way!

One thing that concerns me a little is the warning sticker on the top of the module that states:

"INITIALIZE THE VSC COMPUTER ACCORDING TO THE REPAIR MANUAL BEFORE SERVICING."

The only thing I knew about initializing the VSC computer was pulling the battery for at least 5 minutes after an alignment. Is there something else I should be doing?