Will a P3030 trigger a P3000 code? (2001 Prius)

Hi Ryan,

Yes. DTC P3000 is logged by the hybrid vehicle ECU, and means that the traction battery ECU is reporting a problem.

Since DTC P3030 is logged by the traction battery ECU and implies a broken voltage sense line, there's a good chance that if you can fix this, that your car will be restored to normal operation. Please take photos of the bus bars and post, along with the broken sense wire if/when you determine which one failed.

Good luck.

 

Patrick is right and I would only add a suggestion to pull the sense line plug and check for corrosion. There have been two reports of corrosion in the socket and plug. The good news is you can run a jumper around to solve a corroded connector. Just try to remove any latent electrolyte so the corrsion won't proceed.

Bob Wilson

 

No. P3000 is logged by the HV ECU after it receives fail-safe data from the battery ECU, as opposed to looking at codes in the battery ECU. Fail-safe modes do not always occur at the same time that codes are set. The root cause of both codes may be the same; it is difficult to say for sure without information codes and additional data.

Yes, there is a chance of this. I recommend that you diagnose the P3030 first.

 

Did you use a digital ohmmeter to verify continuity of each sense wire (I believe there are 20 sense wires in total) between the metal terminal that connects to the battery module, and the wiring harness connector that plugs into the traction battery ECU? You'll have to look at the color coding of each sense wire and find the two ends, one at the bus bar and the other at the wiring harness connector.

I suggest that you make a table that shows the color of each sense wire, and the resistance that you measured, and look for one reading that is larger than the others. (Also, connect the two ohmmeter test leads together to see what resistance is contributed by the test leads.)

Do you see any corrosion within the wiring harness connector or the mating socket in the battery ECU? Any corrosion of the sense wires?

The problem is likely to be subtle, so you'll need to keep looking until you find it. Good luck.

 

I think that vinegar is OK for cleaning the bus bar that doesn't have sense wires attached. I'd be concerned about using a chemical bath for the bus bar with sense wires as the chemical might wick up between the copper wire and the wire's insulation and remain in place over time.

You might be right about measuring each wire becoming an exercise in futility - but if you can't find a problem with a sense wire then the only other possibility is that the traction battery ECU is bad. So it would be good for you to be 100% confident that the wiring is good, before you go to the effort of trying to find a replacement for the ECU.

 

Toyota sells replacement buss bars and sense wiring harness. I understand they run a little over $100 but it would eliminate any questions of corrosion residue.

Excellent photos although the prospect of working 'in the car.' Well I'm a little large.

Bob Wilson

 

Hello everyone,

My name is Nick, from Seattle. I am a first time Prius owner. Bought my 2003 Prius about eleven months ago. I am having an electrical problem as a couple of day of now. Several things, like check engine sign, triangle with exclamation mark in it, a car symbol with exclamation mark. After taking it to the dealership, testing came back with P3000, P3030, C1202, C1213, C1215, C1241,C1242, C1259, C1551 - any idea what these might mean. They told me that has something to do with a HV battery and that in its turn causes all these other error signals. However when I look at the battery funtionality of the dash boards, everything appears good as before. The car drives fine, sometimes powering down. If I pull over and restart, it goes again. Please help if you can, any advice?

 

This is the exact same message cut-and-pasted over and over again. Regardless, do you have tools and feel comfortable working on cars?

Bob Wilson

 

I just ran into the same problems with an 01. I replaced the inverter with a used one from the junk yard. It solved some of my error codes and messages (P3125 I think was the code) I also replaced the inverter cooling pump as this had never been done and it wasnt working. I suspect this is why the inverter quit working in the first place. I still had the pesky P3001 and P3030. The dealer replaced the battery and sensing wires along with the hybrid ecu and battery ecu. not the problem I still had the codes. After months of diagnosis and quite a bill from the dealer, they determined that the MG1 is partially bad causing the codes and reduced power on acceleration and the ICE to run all the time. I hope thats not your problem, but its something to think about. Check the Inverter cooling pump (you can see the coolant moving in the resivoir)and replace it ever 100k miles as prevenative maint. It could be why my transmission went out and my inverter. just FYI