P3030 and burned ground wire in HV batt. ECU

Hey folks,

I've seen a lot of p3030 threads in my searches, but did not see my specific condition addressed.

I have a 2005, 150k miles, bought it running and driving, but the emergency lights were all on.

took it apart, discovered there were rats living in the car and they'd chewed through some wiring.

I repaired the wiring correctly with solder and shrink wrap, resistance values are acceptable, I pulled the HV battery, checked it out, and here's what I found:

1.) the cells were all at about 8.5 volts- way overcharged from what I understand, but I could tell they had been replaced sometime recently with either used or reman. the

2.) not a single wire in the HV harness anywhere on the car had been chewed by rats, just the rear immobilizer, both rear wheel speed sensors, the ground going to the 12v charger outlet in front.

so I put the battery back in:,

1.) no start, the display and everything is fine, the inverter starts to cycle, but the car itself wont
go into full operational mode, only in neutral and park.

2.) still have p3030 ( communication failure between HV batt and hv batt ECU)\

SO, I pulled the batt again, took off the harness going directly to the HV batt, the one with all the colored ground wires connected to the battery. I discovered that at the location where the harness clips into the
ECU, had a burned ground wire on the connector, it literally just burned and melted. this affected of course its resistance and the resistance on the several wires near it, everything else on the gorund harness was just fine as far as resistance.


my questions are as follows:

1.) has anyone ever heard of a similar case, and if so, what was the verdict? WHat could cause this ground to get so hot it melted the connector?

2.) has anyone found a wiring diagram to a diagram of the pins on the ECU itself, and if so has a method been established to test resistance between pins on the ECU to determine if its still viable?

so, ground was bad, voltage in cells was high, what happened, and can the batt ecu be tested f
or viability prior to reflash?

 

I haven't looked but im hoping there's a digital copy of the FSM somewhere online.

damn I didn't think of that about the safety plug, I mean I wasn't too intently watching it, I just stuck it in, and I locked the lever but do not recall going up then straight down necessarily. im gonna order an ecu and that section of harness anyway.

just out of curiosity, why cant it be reflashed, is it simply not something Toyota makes updates for?

I am using an OTC genisys touch, with otc vci

thanks a lot for the help!

 

yes I have an autobody shop and need the reader for reflash and general diag. never heard of a 25 dollar mini vci, god all vcis out there that ive seen are between 1200-2500, im gonna look that up. you should be able to rent techstream for like 24 hours or a week or something im sure so ill look into that.

this is a really great forum, thanks for the help man