01 p1636 and p3002

DTC P3002: HV ECU communication malfunction. The traction battery ECU and the hybrid vehicle ECU are not able to pass information; this code is reported by the traction battery ECU.

DTC P1636: HV ECU malfunction, reported by the engine ECU.

So it sounds like the hybrid vehicle ECU is having a problem. That is located on the floor, front passenger side of the car. Was the car in an accident or was it flooded?

The traction battery is behind the large lump that runs along the back of the trunk, visible when you open the trunk and look inside. Remove the trunk liner trim to gain access.

Can the car be driven? What driveability symptoms exist?

Suggest that if you plan to DIY, you obtain repair manual at techinfo.toyota.com so that you can find the troubleshooting steps associated with the DTC, and don't damage the car or kill yourself. High voltage is present wherever you see the orange insulated cabling. Good luck.

 

Your GF's car has serious problems and needs serious help. You will need the correct factory repair manual info if you expect to be successful. Paper manuals for that car will cost around $300 from the Toyota dealer.

I do not think the CD will be useful. It might be an illegal copy of the Haynes manual which is close to useless.

If the battery charging is not occurring according to the normal pattern, then your GF might be damaging the traction battery by continuing to drive the car. Suggest that you try to fix the problem as soon as you can. Good luck.

 

get the 12 volt battery checked, it might be bad giving the ECU erroneous readings

 

If you need to replace the hybrid vehicle ECU, it might be necessary to register the ECU with the immobilizer ECU or else the car will not start. This will require the Toyota diagnostic laptop.

Hence the need for you to consult the repair manual before you plan your work, so that you can decide what work you can reasonably do yourself.

The 12V battery is located in the left side of the trunk, behind the piece of trunk trim secured with four fasteners.

Your local Toyota dealer should be able to access the service history of work performed by any Toyota dealer, based upon the VIN.

 

OBDII data port

 

You mean the right side, passenger side of the trunk.

 

No, the Classic 12V battery is on the left side (driver's side). This is why the Classic battery terminal polarity is reversed from 2G and 3G battery polarity.

With the battery positioned so that the terminals are closest to you, the Classic battery has positive on the right and negative on the left. 2G/3G battery terminal polarity is the opposite.

 

I can agree with the 12v battery issue. I was throwing the same codes (intermittently) just before the battery croaked. New battery and codes have never reappeared.

 

I have said again and again if you take the car to dealer like many people here suggest you will get what they will give to you. Ridiculous repair charge

Fix it yourself that is why Prius forum exists. Search for problem car in Gen1 Prius you will see i describe the procedure to reset the immobilizer if you replace the hv ecu. I went through the headache, anguish and time wasting for your benefit so use my suggestion or you can pay dealer to do it for you.

 

I did have the weak 12v battery thus causing weir code. Make sure it is well and good before tackling anything else on the car.

 

What error lights do you have on now?

If you restart the car three times, do the error lights go away?

If you have a bad traction battery, there are specific codes and that is what we really need. There are two common faults:

• short to ground - due to failure to apply the TIS that 'sealed' the modules. This one might get fixed by Toyota ... always negotiable.
• failed modules - with the codes, we can actually tell which one or Toyota can read out the position.

Now if you'll complete your profile, there may be someone in your area who has a Graham scanner or one of the sophisticated scanners that can read out your Prius codes. Prius friend Hobbit may know some independent garages in your area that might look at the car with some skill. But the codes would allow us to quickly fault isolate.

Now Tom has figured out how to swap modules and may have some available. There have been mixed results on module swapping this but it is cheap and can provide some relief. Then depending upon how much money you are willing to put in the car, there are more options.

Bob Wilson