P0A9B Hybrid Battery Temperature Sensor Cicuit

Nice work. If there were no driveability issues that provides a good clue that the traction battery is indeed OK.

 

Your traction battery has a warranty life of 100000 miles in most states and 150k in California. And their are lots of tech centers selling refurbished batteries. And a guy in Tampa sells this charger to equailie the cell

 

but the o/p said the car had 170k, and the battery was fine.

 

Another resurrected thread, almost at 4th birthday. LOL.

 

Does this imply that that module does not need to be VIN flashed? That it can simply be replaced?

 

There are around a dozen-plus different ECUs in a gen 2 Prius—more like a couple dozen in later gens—and only a few of them care at all about the VIN or what car they're installed in. By and large they're just plug and go.

 

So what ECUs *do* care about the VIN and therefore need flashing? I am having massive problems and intend to replace the HV Control ECU (part# 89981-47211 / 89981-47212), the Engine Control ECU (part# 89661-47160 / 89661-47161 / 89661-47162), and the Computer Assy, Battery / Computer Assy, Soc (part# 89890-47071 / 89890-47073).

 

The engine control ecm will need a vin flashed and you will likely need the immobilizer ecu reset and configured for your keys. Some online sellers will do the vin and update firmware as part of the deal.

If this is a result of a reverse polarity jump, the odds are good the ecus are still good but some fuses were missed or the orange hv disconnect was not snapped in after it was closed.

 

<shrug>

I've plugged in a used ECM on my 2006 and the VIN (as reported by a scantool) didn't change. Didn't have to do anything with security or resets.

The service manual indicates that a handshake procedure is required if you replace the hybrid control ecu.

Posted via the PriusChat mobile app.

 

What kind of problems? What codes do you get? What systems can communicate with your scantool?

Posted via the PriusChat mobile app.

 

After a catastrophic IC engine failure, our 2007 Gen2 sat for 2 months until I replaced the engine. The hybrid battery is now going nuts, quickly changing from 1-2 red bars to suddenly the max green bars, then 1-2 red bars, quickly climbing and descending through the blue bars. Every start throws multiple dash warnings, including the Red Triangle of Death. Cheap ODB scanner plugged in for repeated clearing of codes.

Worst part is, when it throws codes, it often also revs the engine to the max RPM and stays there. I have to pull over ASAP, clear the codes, shut the car off, turn the car on, clear the codes again, then resume. So, something is obviously causing a misreading of the throttle position.

I'm attaching TechStream screenshots of the pages showing readings where error codes are. One or both of the cells in the hybrid battery blocks #4 and #12 clearly need replacing. No problem with that, as I've replaced bad cells twice before.

My question is, should I be replacing any ECU? I have a replacement Engine Control (original is part# 89661-47160; salvage is part# 89661-47161). Once the hybrid battery is out and disassembled, does anything in these screenshots indicate that I should also replace the Computer Assy, Battery (assuming original is part# 89890-47071; salvage could be part# 89890-47072 or 89890-47073) and/or the HV Control (assuming original is part# 89981-47211; salvage could be part# 89981-47212)?

Also, does the 'Engine and ECT' status being "Inc" mean that that module is dead = no communication with TechStream at all?

 

Can that be done with the 30-minute jumper between the ODB port pins #4 and #13 trick?

 

What RPM? Can you use your scan tool to read the RPM at that time? I've seen posters exaggerate and say something sounded like max RPM when it wasn't really close. I think max on a gen 2 is around 5000.

Is it really "obvious" that's the reason the car has increased the engine RPM? Or would it be more accurate to say an increase in engine RPM is observed, and the reason hasn't been pinned down?

I've read on RC forums that the NiMH chemistry is exothermic when charging, endothermic when discharging. If the battery has been measured as hot, one way the car can cool it is by using power from it (at a moderate rate; too much, and resistive heating would outweigh the chemical cooling). The car can do that by using some battery power to twirl the engine at a higher RPM.

If this is a protective move in response to sensed battery temperature, there might be little benefit in going to such lengths to thwart it.

 

When the car is traveling at any give velocity, you suddenly get the Red Triangle of Death, the weird circle with 2nd arcs on both sides and ! in middle, and the Engine Maint light, and the engine jumps to a *much* higher RPM, and stays at the *much* higher RPMs, through braking to a stop, and stays at the *much* higher RPMs until you shut the car off, then… yes, some module is misreading the throttle position and deciding that the throttle is being floored. And I mean floored!

 

I take it when you say 'throttle' here you mean the accelerator pedal. People often loosely call both the 'throttle' (as, in other cars, one is usually connected to the other) but in the Prius it pays to be specific, because the throttle (on the engine) and the pedal (in the cabin) both have their own position sensors that have to be read by modules. (Different modules—the throttle position sensor is wired to the engine control module, while the pedal position sensor is wired to the HV control ECU).

Your conclusion that the HV control ECU is misreading the pedal position as floored is easy to test. Connect a scan tool while this is happening, pull up the HV control ECU live data list, and report the readings ACCEL POS #1 and #2.

(The accelerator pedal in fact contains two independent position sensors, which is why there's a reading #1 and #2. If the module ever sees the readings not in sync the way they should be, it knows there's an error and enters a limp-home mode.)

While connected, the same scan tool can be used to get the trouble code(s) to identify what issue(s) the car has detected. The live data list can also show what the engine RPM is, so "*much* higher" can be pinned down better.

 

No, not based on any of the data you have posted so far.

Nope. The only reason to replace the battery ECU would be if any of the pins in the orange socket on the ECU were corroded. If you found that, you would replace the battery ECU and the voltage sense harness (call the No. 2 frame wire) to ensure a long-term reliable fix.

Nope. Inc is an abbreviation for incomplete. The ECM has not has enough time or drive cycle conditions to complete all of its monitors.

Nope, that is not necessarily the correct conclusion. ChapmanF had a possible explanation.

You haven't touched on the two codes that would be the ones I would be focused on and that is the P0A80 and the P3022. Clearly, the battery is not happy. In addition there really should be a P3014 because block 14 is not happy either.

You have at least 2 modules to replace and then a reconditioning of the pack, if that is the way you want to go but it is a lot of work for maybe 2 years of extended life. For me, if I was in this position, it would be a shiny new pack from Toyota then be done with it for the next 12-17 years.

 

^^ agree 100% with dolj

 

Please tell us about the battery module replacements that you previously did. When did you do the first replacement, and how long after the first replacement did you do the second replacement? How long has it been since the second replacement?