EXCESS 12v LOAD WHEN OFF - DRAINING 12 VOLT BATTERY

[davewill]

Had to replace my battery last week. Went on vacation and 5 days without being driven resulted in a dead battery. Since I was at 34k miles and 2.5 years, I figured it was time to replace it so I just picked up a new one at Costco. I could have tried to get the dealer to replace it under the 3yr/36k bumper to bumper, but it honestly wasn't worth my time to drag it in and deal with the dealer when I could have the car back up and running for $70 and a half hour of my time.

 

[smkettner]

Picked up the car today. All Irvine Toyota could do is replace the 12v battery one more time :roll:
Just measured the vehicle draw after parked 30 minutes. Same 2 amp draw.
I assume it will be back on the tow truck next week.

Should I call someone at Toyota? Who do I talk to?

 

[TonyWilliams]

Picked up the car today. All Irvine Toyota could do is replace the 12v battery one more time :roll:
Just measured the vehicle draw after parked 30 minutes. Same 2 amp draw.
I assume it will be back on the tow truck next week.

Should I call someone at Toyota? Who do I talk to?

Obviously, they are completely clueless. This isn't troubleshooting; it's guessing (badly) and part swapping.

I would find the current draw. It won't be that hard with a few simple tools and a few hours of time.

 

[smkettner]

It is fuse #9, G/W-B 10A Multiplex communication system. When pulled first this drops about 500 milliamps. (I speculate this draw could be normal)
Next is fuse #10, RADIO 30A Audio system. When this fuse is pulled next... current drops to virtually zero. (this has to be wrong)

When these are reinserted after about 60 seconds the current draw remains at zero.

Restart the car. Let idle in neutral 60 seconds and shut down.
Withing two minutes of varying 3 to 6 amp draw the car is back to sleep at 2 amps draining from the battery.

Anyone have a healthy vehicle to compare this to?

 

[smkettner]

Dealer is replacing an ECU today. Should be ready on Tuesday. Fingers crossed.

 

[TonyWilliams]

Dealer is replacing an ECU today. Should be ready on Tuesday. Fingers crossed.

Another guess? Or, they actually isolated the power drain to this device?

 

[smkettner]

Dealer says they talk with Toyota engineer (via phone?) to assist in the diagnosis and get approval for warranty repair.
I have no idea what was tested or the results. Customers don't really get to talk with the technician.
I did give the service writer my findings.... again.

Will see what the bill says on Tuesday. Service writer said it was a $4,000 Toyota part available locally.

 

[miimura]

I'm guessing that they will change the NAV head unit.

 

[TonyWilliams]

Dealer says they talk with Toyota engineer (via phone?) to assist in the diagnosis and get approval for warranty repair.
I have no idea what was tested or the results. Customers don't really get to talk with the technician.
I did give the service writer my findings.... again.

Will see what the bill says on Tuesday. Service writer said it was a $4,000 Toyota part available locally.

I would keep EVERY scrap of paper of this exchange, including what you told them and when.

Particularly if the ultimately replace the Nav unit.

 

[smkettner]

Paperwork says Gateway ECU replaced. Only drove it home and the displays work perfectly again.
I believe this would be covered under the 60/60 drive train warranty.

Kills me to buy the extended warranty just to get 36 months and possibly about 60k extra miles.
I suppose it will be easier to sell when the time comes. Rather put the money toward a Tesla.

Can't believe I have been having this issue since February and a bit before.

This is the part listed: http://www.overstockoemparts.com/oe-toyota/898810r011
Doubt a shade tree guy can replace this without some equipment to program.

 

[miimura]

I don't get it. You know the price of that one part that was replaced on your car costs more than the warranty, but you don't want to buy the warranty. I really like the RAV4 EV, but there's no way I would keep one without coverage outside the bumper to bumper warranty. I've never bought an extended warranty on a car before, but I feel there is ample evidence that I will get my money's worth within the 8 years and 100,000 miles of the Toyota Platinum Warranty.

 

[smkettner]

Yes that is true. The only repeat issue I keep hearing is the transmission noise.
The rest seems to get fixed and stay fixed.

Warranty may say 8yr 120k but half that is already covered.

 

[Aries]

Suddenly my RAV appeared with a flat battery the other day. This is after having sat for two days. The battery in it is only 6 months old and was fine when tested (yesterday).

I threw an ammeter on there when the car was quiescent and saw current readings between 0.50a and about 2.50a. Most of the time was spent > 2a. I left the ammeter connected for about half an hour to allow for possibilities that maybe the car needed to 'settle down' after having the 12v reconnected and "rebooting". Current drain pattern remained the same. The car was not connected to the EVSE and nothing was going on -- lights out, doors locked, traction battery fully charged, cool outdoor ambient temperatures (san diego), and no sounds of motors (i.e. coolant, etc) running.

This feels like a high amount of current drain. Does anyone here have any comments on this? I found another thread about current drain which was resolved with replacement of an ECU but I didn't come away with a clear answer from that as to what the current drain should be.

Anyway, I did the pull one fuse at a time until it goes away deal and ended up with the fuse called PM-B. Pulling that reduced the current drain down to the 0.50 range where it stayed. Re-inserting caused the current drain to return back to the >2a state. What is a "PM-B" and does anyone here have any thoughts as to what that might mean?

This car does have a JDEMO installed but I don't have any reason to suspect that. However, Tony, if there is a way to temporarily isolate it I might be inclined to do so just to rule that out.

Thanks for any comments!

 

[smkettner]

I assume you read my thread on 12v battery drain issues.

http://www.myrav4ev.com/forum/viewtopic.php?f=7&t=1775

Now that the computer is replaced mine drops to less than 50 milliamps within 3 to 5 minutes.
Was a solid 2 amps when malfunctioning.

PM-B looks like passenger side fuse box #24 "Power Management System"

I never pulled fuses inside but just those in the motor compartment. For me some combination of 9 & 10 would stop the battery drain. These are Multiplex Communication System and Audio System. The computer was apparently not shutting down these items. I was having display issues for many months and eventually failure to charge. All is now back to like new operation.

 

[Aries]

Yes, that is the thread I reviewed. Thanks for the info. I'm not sure what to make of it as I have not had any problems at all, literally, ever, with the car outside of the well known charge timer thing.

There are no other issues I've observed so far except this draw. If I connect the fully charged battery up.. everything works -- displays, EVSE/Charger, it starts and drives, etc. I just have a 2a drain that will run the battery flat in a day or two...

I wonder if there is a "reset to factory defaults" for the ECU / "computer" that maybe I should try?

The PMB fuse was located in the motor compartment. Linked are some relevant images.

 

[smkettner]

Funny, I never opened that box. My description was right I just assumed it was inside. "Power Management System" #24 listed in the manual.

 

[TonyWilliams]

This car does have a JDEMO installed but I don't have any reason to suspect that. However, Tony, if there is a way to temporarily isolate it I might be inclined to do so just to rule that out.

Thanks for any comments!

It's easy to disconnect JdeMO from the low voltage harness. DO NOT ATTEMPT TO DISCONNECT THE HIGH VOLTAGE UNLESS YOU KNOW WHAT YOU ARE DOING !!! INJURY OR DEATH IS POSSBLE !!!

Start at page 20 in the installation instructions. I recommend disconnecting the 12 volt battery PRIOR to moving these plugs, as you might get a "CHECK EV SYSTEM" error otherwise.

Remove our low voltage wiring harness from the Tesla onboard charger, and then plug the Toyota chasssis wiring harness into the onboard charger (as originally configured).

It's not easy to do, because you can't see the receptacle on the Tesla onboard charger.

Here’s a link to "JdeMO Installation Manual RAV4 EV":

https://www.dropbox.com/s/bgzq16qi65lorq7/JdeMOinstallationManualRav4EVpaperA4.pdf?dl=0

 

[asavage]

It's a shame that Aries didn't post the conclusion to this saga.

[later]

Aries posted later that the problem was caused by a GPS tracking device plugged into the OBDII port, which prevented the Toyota from sleeping some systems.