New HV-ECU

Sorry to hear of your troubles.
Great on getting it to the dealer with the gun still smoking!

FYI - the diagnostic manual indicates that code 3115 is generic to the System Main Relay, and is specific to a HV battery current sensor malfunction. The current sensor is located in, and part of the system main relay assembly and sends HV battery current data to the HV ECU.
Main diagnostic code 3115 may be supplemented with one or more of the following inf codes:
224
SMR Cont1 malfunction: Open or +B short in system main relay No. 1 circuit
225
SMR Cont1 malfunction: Short in system main relay No 1 circuit
226
SMR Cont2 malfunction: Open or +B short in system main relay No. 2 circuit
227
SMR Cont2 malfunction: Short in system main relay No 2 circuit
228
SMR Cont3 malfunction: Open or +B short in system main relay No. 3
229
SMR Cont3 malfunction: Short in system main relay No 3 circuit
230 - no 230?
231
Deposit of SMR: system main relay + terminal deposited
232
Deposit of SMR: system main relay - terminal deposited
233
Deposit of SMR: system main relay + & - terminal deposited

Interesting that in the specific diagnostic steps, the following is described:
Check the wiring harness,
- If inf codes 231, 232 or 233 - replace HV ECU and SMR
- Otherwise replace the HV ECU
If inf code 231, 232 or 233 AND inf code 224-229, replace the HV ECU.

I'd be REAL interested in the complete code and exactly what they replace, including the revision code.

Good luck and keep is "in the loop",
bp

[%sig%]

Harry,
Thanks for your response. Here are my thoughts. There is not much chance of getting an exact replacement for a July 2000 build HV ECU. Computers are always a "work in progress". Nothing when released is ever really done. The managers just say "no more changes now we gotta get this out the door." Any further changes have to wait for the next release/revision. Hardware, software its all the same. As minor bugs are found boards are revised. We used to physically modify computer circuit boards with jumper wires and foil cuts. Now I suspect that most of the changes are software changes burned into chips. The effect is the same. With a new HV ECU I get the latest version of what the Prius Engineers feel is good to go. Kind of like comparing the first version of Windows 98 to Windows 98SE. When I pick up my car though I will try to find out if the was a part number change between the old ECU and the new.
Mitch

OK folks,
Just got my Prius back from its HV ECU replacement. It turns out that the part number has not changed it is still 89981-47040. Did a search on the groups site on that number and found this post from last year around this time:
[Allen Massey groups post# 8529 http://groups.yahoo.com/group/toyota-prius/message/8529
Sun Mar 11, 2001
A few months back I discussed this problem under the
heading "Surging". I have spent a lot time working with my dealer
and last week we finally replaced the main computer (part number
89981-47040). This seems to have fixed the problem. It took my
dealer two months to get the computer in after placing a special
order. And when it did come in he did not know how to install it
correctly. It turn out that you need to take a copies of your keys
when they replace the computer because they must reprogram the new
computer to accept your keys (this takes 45 minutes per key)

What he told me was if the version number of the software in the
computer is 5 or less then you may have the surging problem.

So my recommendation is for everyone that is having this problem to
force your dealer to replace the computer as soon as possible. This
is something you really do not want to pay for yourself since the
computer cost is about $2,000.]

My question to the group is where is the ECU located and has anybody seen the version number on theirs?
Mitch
BTW the work order says: PULLED CODE P3115(SMR) INFO #1 (224)
(NEEDS RE-MODIFIED HV ECU)
PERFORMED TSB EG009-01.REPLACEMENT OF HV ECU.
PREVIOUS PART# 89981-47040. REPLACEMENT PART# (SAME)T

OK folks,
Just got my Prius back from its HV ECU replacement. It turns out that the part number has not changed it is still 89981-47040. Did a search on the groups site on that number and found this post from last year around this time:
[Allen Massey groups post# 8529 <http://groups.yahoo.com/group/toyota-prius/message/8529>
Sun Mar 11, 2001
A few months back I discussed this problem under the
heading "Surging". I have spent a lot time working with my dealer
and last week we finally replaced the main computer (part number
89981-47040). This seems to have fixed the problem. It took my
dealer two months to get the computer in after placing a special
order. And when it did come in he did not know how to install it
correctly. It turn out that you need to take a copies of your keys
when they replace the computer because they must reprogram the new
computer to accept your keys (this takes 45 minutes per key)

What he told me was if the version number of the software in the
computer is 5 or less then you may have the surging problem.

So my recommendation is for everyone that is having this problem to
force your dealer to replace the computer as soon as possible. This
is something you really do not want to pay for yourself since the
computer cost is about $2,000.]

My question to the group is where is the ECU located and has anybody seen the version number on theirs?
Mitch

BTW here is the wording on the work order:
CUSTOMER STATES CHECK ENGINE LIGHT ON
HYBRID WARNING INDICATOR LIGHT ON/MASTER HYBRID INDICATOR
LIGHT ON ALSO. VEHICLE RUNS FINE THOUGH
PULLED CODE P3115(SMR) INFO#1(224)
(NEEDS RE-MODIFIED HV ECU)
PERFORMED TSB EG009-01. REPLACEMENT OF HV ECU.
PREVIOUS PART#89981-47040, REPLACEMENT PART# (SAME) T

Yes, I've seen mine. Anyone who has installed Coastaletech's remote cruise control has seen their main ECU, because you have to lift it up to tap into the wires. It's located underneath the front passenger's feet, where the floor slopes upward. It's pretty easy to get to: remove the passenger scuff plate on the floor by the door, remove the plastic thingy protruding from under the dash near the door, peel the carpeting back, unscrew the metal plate protecting the ECU (you nee a 10mm deep socket), and you're there!. As I recall, mine had a sticker on it with a big "5" which tells me I have software version 5. My car was delivered 9/1/00 and definitely has the surging problem. I consider it a minor problem since I don't do much highway driving, and even when it occurs the surging goes away after a minute, so I haven't had it replaced yet. I figure I'll wait a while so that when I get it replaced I'll get a more recent software version. I may not wait beyond the third year since I don't want to risk an argument over whether it's still covered under warranty. A photo of the Technical Service Bulletin on "surging" (EG00601) is in the files/technical section of [email protected].
Sam

Mitch asked:
> My question to the group is where is the ECU located and has anybody
> seen the version number on theirs?
The HV-ECU is located below the passenger's "foor board". Pull the passenger carpet and look.
There is the part number tag and a separate (round?) single-letter sticker: A, B, C...
Someone NEEDS to take / post a picture of this.

Guess I'll have to go snoop this weekend - if it's warm anough.

bp

[%sig%]

Well, the plot thickens. After exposing the HV ECU (great instructions Sam) I discovered what I suspected was a typo In the parts section of the work order was actually correct. The old ECU was a 47040 (probably version 3,4,or 5) the new ECU is a 47060 version 1.

LABOR
CUSTOMER STATES CHECK ENGINE LIGHT ON
HYBRID WARNING INDICATOR LIGHT ON/MASTER HYBRID INDICATOR
LIGHT ON ALSO. VEHICLE RUNS FINE THOUGH
PULLED CODE P3115(SMR) INFO#1(224)
(NEEDS RE-MODIFIED HV ECU)
PERFORMED TSB EG009-01. REPLACEMENT OF HV ECU.
PREVIOUS PART#89981-47040, REPLACEMENT PART# (SAME) T

PARTS
1 89981-47060 COMPUTER, HYBRID


All the info on the new ECU:

[Bar Code]
89980-470601
HV CONTROL
TOYOTA
89981-47060
12V MADE IN JAPAN
1

[%sig%]

Re: New HV-ECU - got it fixed

I had the same experience. First time was in December (first really cold weather here in Colorado for this season). By the time I got it to the dealer, they couldn't find an error code in the computer so they called it a "phantom problem" and sent me home. Problem occured again in January...I took it into the dealer with the error still showing, made them check for an error code immediately. After researching with Toyota they told me this was a known problem and the engineers at Toyota were working on the software patch for the ECU. They said they would call me when it was available. Last week I took the car in for its 18 month checkup/maintenance and asked about the ECU. They were able to install the new ECU (cost of new ECU incl. labor is about $900 according to dealer paperwork I peeked at!) that day.

To others, the error did not occur during my first winter with the car, but was quite consistent this year. When the error occured, the engine would usually turn off and not want to come back on. I would drive 100 yards on battery and then turn car off/on. Engine would start. After driving for 10-15 minutes, car was totally back to normal (something warmed up??!!?) until the next time it got properly cold (10 degrees F or less I'd say).

So far so good with the new ECU but we haven't had really cold weather again so who can really tell...