Hybrid battery failure (again)

You probably broke a wire in the bus bar harness, just get a new or used replacement

 

How old is your 12v battery? I know you said it's fully charged, but have you done a load test?

 

Have you? Do you have techstream or a phone app like Torque or Hybrid Assistant, etc that allows real time monitoring of block voltages so you can see what the ECU is seeing?? Your 3030 code is not signalling a bad module. It's signalling a bad wire or connection. Connection would mean either end of the wire, Search P3030 and you'll probably find this online:

P3030 translates to “High Voltage Line Snapped”. It sets whenever the HV Battery ECU detects an open circuit to one of the battery blocks. The Prius battery has bus bars that run down either side of the pack, to connect the modules in series; on one side of the battery it also runs “sensing wires” to each bus bar (effectively monitoring every two modules, which it calls a “block”). This is how the computer keeps track of total battery voltage (by summing the values of all the blocks) and the balance of those blocks.

(Pic of “freeze frame”, a data snapshot, when P3030 set. Note the loss of voltage reading at block 10 (0.83v), but also that the car substitutes a max voltage value (20v) at the previous block, 9. I am not sure why this is the case, but it happens at whatever block is just before the one with the broken wire. I assume it has something to do with how the ECU calculates voltage from one block to the next, but it also makes sense that it would max another value to help compute total battery voltage.)

 

I have a 2004 prius that I took the bus bars off the battery to clean, put it all back together, and now I'm getting this code. Feeling frustrated and I don't know what to do.

 

All the bolts are torqued properly and the orange plug is seated correctly woth the fuse intact?

How much corrosion was on the bars in your 2004?

 

My bus bars were very corroired. Orange safty plug in installed. My car will start but the engines runs constantly

 

I’d get Techstream or a way to look into the information available from your Prius .

If you log into the tech info site from Toyota and pay $15 for 2 days, you can get information on the code as well as the troubleshooting tree.

I’d also ask for the printout from Toyota as to what the other codes are.

Good luck and keep us posted .

 

Check your individual block voltages. Did you have any extra terminal nuts? All hand tightened?

 

Blocks lookes good, no left over nuts, used a hand drill to tighten them down, then manually checked by hand. Also grid changed once it was all put back together.

 

The torque spec is 48 inch pounds. You think you exceeded that?

 

Possibly! Nothing was broken, but would over tightening cause problems like this?

 

It's very unlikely you could have broken a module terminal by hand tightening. 46 inch pounds is around 1/8th of a turn after it's tight. Not much to it.

You can loosen them all and see if any terminals fall off (seeing you'll most likely have to disassemble to find the broken wire). You'll probably need a new bus bar harness

 

New bus bar harness needed

 

Everyone is sure that this has nothing to do with that "final push" to lock in the giant orange service plug? For Gen 3 you do the 90 degree and then the final slide in to lock in place and connect the wires. Not sure about Gen2. Not doing the final slide will not yield any voltage.