2001 Toyota Prius Questions

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MG2 replaced with new one. Reverse moves forward and drive moves backwards, so Polarity is reversed. I have racked my brain to figure out why. The only thing I can come up with is the stator itself isn't wired correctly. Any ideas?
My battery recently died so it reset the computer in my car. I was told I need to complete a drive cycle for my car so that I can pass the emissions test. Each car is unique in the drive cycle and how to do it. Does anyone know how to complete one for a 2001 Toyota Prius?
The display buttons work the climate control buttons work but the radio buttons do not work is there a quick fix? I have checked every fuse for audio and change them out also checked all connections in the back of the radio and still nothing working do you recommend anything else or is my radio broke?
this is the second time in a row this car lost power and shut down. hoping someone can point me in the right direction on what to replace first then second etc. Thanks in advance for whoever can reply. kc>>
After starting the car and entering traffic, I noticed that the dash was black and the fuel consumption screen was not giving any indication of fuel use. after 5 minutes the screen did show energy recovery by regenerative braking, but no histogram and no fuel consumption info. When I got home I could not shut the car off. The engine did not run, but the console display remained lit up. I disconnected the auxiliary battery, inspected fuses and finding none blown I reconnected the battery. The console screen lit up again, but so did the dash. When I hit the switch everything shut down. When I hit it again, everything started normally.
In essence, rebooting the system seemed to solve the problem but I am left wondering why it happened and will it recur when my wife takes the car to Georga in Nov? Should I just give her a socket wrench with a 10 mm socket and tell her to disconnect the ground cable then reconnect it again or is there an easier way to reboot?
This has happened 3 times now, and the codes said that it was a power inverter problem. I had the power inverter replaced, but it happened again. Why is using the A/C causing this problem?
Just about 4 months ago I got a stupid idea that I wanted to learn about the Toyota Prius. I couldn't find any classes locally at any of the colleges.
I bought two 2001 priuses to serve as my text books so too speak, both had bad HV Bats, I got lucky on the first one, it had been rebuilt within the lat 2 years an had all 2nd Gen Modules.
I replaced 1 module at the cost of $40 and that one runs great. The second one had set for a year or two and I had to replace all 38 modules out of 2 07 bats. Both batteries perform very well. the second prius had a secondary problem. I could charge my HV Battery up to the highest level that the prius would charge it. I would then reinstall it in this problem prius. I would start the problem Prius and enter the Ready mode, the Energy flow screen would show energy flow from the ICE to the electric motor an then to the HV Battery, which looked completely normal. The problem was that the HV Bat was being drained rather than charging up.
I put a analog volt meter on the HV Bat put it in the 500 V range, in the Ready mode the Bat was being pulled down from 300 V to 240 Volts an after a few minutes the devils triangle would come on an it would tell me I had a HV Bat problem. Stupid car didn't have sense enough to know it was never a HV Bat problem. I just replaced the complete transmission along with MG1 an MG2. I had megged out the MG1 an MG2 stators to chassis or ground an got near an infinite reading. I didn't bother with milliohm meter reading since the 3 winds are in parallel and me not being sure if I would need to measure AC impedance or just DC ohms for the test. I figured the resistance would be so low as probably not a good reliable test.
I bought a transmission for $400 and replaced both MG1 & MG2.This solved my first problem. After replacing the transmission an trying to start it I couldn't get it to run. I learned real fast what just one bad igniter will do. After replacing one igniter I now maintain 300V in the ready mode and the car runs out pretty good.
My problem now is that I have a code P1636 HV ECU malfunction. I assume it is the ECU under the passenger side around the glove box and not the HV Battery ECU.
Am I thinking right??????? Also if I swap out the HV ECU do I have to jump between pins 4 an 13 of the DLC for 30 min with ignition on to set up the hand shake with the immobilizer ECU????
I think before I do much more I will put it the rest of the way together. Right now I just have 4 bolts holding the HV Bat in position an still need to put the cover on it an hook up the cooling fan an vents etc for HV Bat. I was also getting the code P3077, Yea , I guess I could have a problem with my HV cooling fan since it's not connected or hooked up'
I suppose I am a little doubtful that the P1636 for HV ECU malfunction will go away after I got everything hooked up.
Have any helpful ideas for me????
Thanks, Hank
I used a megger meter to test my MG2 in a first generation prius. I have measured from the 3 winds to chassis an get near 200 Meg ohms.
I measure resistance between the winds an I get like 2-3 ohms.
I know there are 3 winds an they are in a parallel circuit with one another.
What I don't know is how to tell if the winds are shorted within themselves or each other.
Does anyone know what the resistance should measure in a healthy stator winding?
Appreciate any an all help I can get here.
Thanks much, Hank
I just bought two 2001 Prius with the intent of learning how they work.
The first one I was able to rebuild the HV Battery myself at a cost of $40.
I got lucky on that one, only one bad module. I bought one off eBay for $40 from a 2007 second generation battery. The second Gen is a much better battery an has a longer life than the first Gen.
So, first one success.
The second one I bought from a junk yard an every one of the 38 modules were bad.
The best one measured .2 Volts.
I replaced all with 2007 modules. The 01 has 38 modules, the 07 has 28, I had to use all modules out of one battery an 10 out of a second 07 battery.
So I was able to successfully rebuild two HV Batteries and at a total cost of $1040 for the two.
My problem was an still is that the second Prius will start an run normal for a few minutes. The energy flow screen shows the ICE sending energy to the MG1 and from MG1 to the HV Battery. This part is all normal. However it is discharging the HV Bat rather than charging. After a few minutes the ICE will shut down, main battery problem lights up an I get a code of P3010. I can erase the fault code leave it set a few an the HV battery will come back with enough power to go through the same sequence again. I will finally have to take the HV battery out of first Prius which is fully charged an put it in the second prius. The HV Bat. that I just ran down I put in the first prius. The car starts an runs fine on the same HV Bat that I just took out of the second Prius that tells me I have a HV Battery problem.
So far I have swapped out the Inverter/Converter, Engine ECM, the battery is changed as a complete unit with the HV ECU an all relays etc. of which all work fine in the first Prius. I have just about exhausted my ideas so far as what else could be my problem.
If anyone knows of anything which could be causing the MG1 to discharge my HV Battery, please let me know.
It seems I have learned a lot in a month of exploring these machines but until I solve this problem I am a looser.
Any help at all will be appreciated.
Thanks much.
Hi there . Do you have any updates ? I have the same problem with my 2001 prius . After it sit for 2 months . I lost the engine battery ( not the hybrid one) the car stars for one minute then shut itself off . I replace both of the engine computer and the hybrid computer with no difference . Need help please
ICE Runs a few seconds, stops an Main battery light flashes.
I did get it to run for a few minutes a few times an the power flow screen showed power flowing from ICE to the HV Battey but as it ran the HV Bat was going down in charge rather than up. It was like the older cars would do if you put the battery in reverse polarity, it would show discharge on the ampmeter and would charge the battery down and not up as it should.
I'm not sure if it would be posible to have a reverse polarity on the HV battery or how it would or could happen? Another Symptom is that when it Stutters an stops an all the Main battery lights come on the Fan cooling motor also comes on until it turn off ignition.
I get a DLC of P1310
The following substitutions have been made with all known good parts:
1- Complete HV Battery along with the relays etc inside the HV battery case, changed out 4 times with known good unit. All work fine in a second 01 Prius I have.
2- Substituted the Inverter/Converter with known good unit.
3- Substituted the Engine ECM with known good. Set up handshake between Transponder ECU an Engine ECM
4-All these Parts taken off the problem car works great on the second Prius.
5- Although I have not substituted the 12 Volt battery, I have charged it an load tested it and it is good.
6-I have substuted the throntle body along with controls etc.
with no change.
7- Fuel pump pressure is 50 PSI an Holds 30 #s for over 30 minutes after turning off.
I think I need some help here, I'm just about up against the wall.
Suppose it could be the radiator cap or maybe I'm holding my mouth wrong when I turn the key? Maybe there is a ghost in the machine???
Can someone please help steer me in the right direction or maybe an idea what to try next????
I feel that I may be an old man by the time I get this thing beat. I guess I sort of forgot, I'm all ready an old man.
72 is not exactly a young buck anymore.
I will appreciate any help I may get and thank you ahead of time for any ideas you can give me.
I have changed the HV Battery back an forth several times with another Prius I have that's working. Both batteries work fine in the working Prius an I have the same problem with either battery in the problem car.

Today I swapped out the Inverter/converter. I started the engine and the power flow meter was showing fully charged HV Battery. By the time I had moved a few things out of the way for a test drive Probably about 2 minutes running time the engine shuttered an Got the HV Battery problem.

So far I substituted the HV Battery, the Inverter/converter, throttle body, throttle position sensor and running out of parts to change out.

I may try the engine ECM next. I really don't want to because I will have to set up the handshake between the transponder ECU and the engine ECM.

I'm not really wanting to do that if I can come up with other ideas that may work.

I've never set up this handshake before an I think I have to short across the Pin 4 and 13 of the DLC an leave it with the ignition on for 30 minutes.

I'm not finding real clear instructions for this procedure. I downloaded directions from the Toyota web site but they had the pin numbers all labeled wrong

and the instructions were Japanese. Like I got to learn their language to work on this stuff?

If anyone has any ideas for me, believe my I would be so appreciative.

Thanks, Hank
My 2001 Prius has set for over a year could have been even 2 years without running because of a bad HV Battery. I have rebuilt the HV battery. The HV battery is now working good.
After charging the HV Battery in a second Pries I have I put it in the problem Prius. It don't matter if I drive it or if I just sit with engine running, in just a few minutes it will shutter around engine stops an I get a P3010 for HV Battery Problem.
The HV battery is good. The one Prius runs great on either HV Battery but this one takes the battery down to a level that gives me a HV Battery problem indication in a very short time.
The energy flow will show the ICE running and the HV Battery as charging but a few minutes later it shuts down with the P3010.
Can someone that knows more than I do, tell me if there are some big electrolytic capacitors inside the inverter/converter that may have lost their ability to do their job or become shorted from setting and causing this problem??? I need some help here guys. It seems I'm in a Texas Death match a Prise an it's winning so far.
I would really appreciate some ideas on this if anyone can help me. Thanks, Hank
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