Headlights, Power Locks, Hazard lights, Cabin Lights, Signal lights ALL WORK -but Cannot Power Car

@Jouxse, FYI, anytime power is lost (due to a flat battery or battery removal/replacement), you need to press the power button twice with your foot pressing the brake pedal. The first press is like IG-ON, so lights all the warning lights in a test mode and powers on the MFD. The second press takes it to READY, all things being equal.

That is nowhere enough to get the 12 V battery anywhere near full. Think more like 20 hours. You also do not need to drive the car, all you need to do is switch it on to READY and leave it in P with the foot-operated parking brake on. Presuming you have a safe and secure place (with adequate ventilation) to do this.

I wouldn't actually recommend this method of charging except for the "you have no other option, right now" scenario. A better option is to put the 12 V on a fully automatic 3.5 - 5 Amp multi-stage battery charger. The good ones will go into a maintenance cycle at the end of charging, so you can just put the car on one of these chargers (and leave it on the charger) anytime you're either not going to be driving it for 4-5 or more days, OR you will only drive it for 3 miles when you do.

 

Well, that's progress. It's not that surprising that you are having trouble with the mini VCI cable, but have you tried the bluetooth dongle with Dr. Prius or Torque Pro? I would expect either of those programs would give you codes that are helpful, although as pointed out, subcodes would not be available. It is pretty likely the battery ECU is reporting one or more weak blocks. Dr. Prius or Torque Pro would show that information. If nothing else, those programs could let you verify that whatever the dealer tells you is accurate.

I'm glad you didn't give up and have at least some reward for your efforts.

 

I just noticed from your pictures you only have 106k miles on the car. With mileage that low, it is probably worth fixing, no matter what it needs. Most of us on this forum have many more miles on our Gen 2's. Ours currently has 287k.

 

Well, there is still some possibility that your HV battery is totally fine, but most of the members of this forum would say that is unlikely if the battery is more than 10 years old and the car has sat unused for a number of months, so here goes...

Different people use the term "battery cells" loosely, but the Gen 2 battery is actually made up of 28 modules, each of which contain 6 cells. The cells within a module cannot be replaced, only the entire module. One block is a pair of modules. If one of the 12 cells in a particular block fails, the battery ECU will report that block as being weak. It cannot tell you which module has the failed cell, only the block number. The blocks are numbered from 1 to 14, beginning from the passenger side of the battery. If you get a code saying one of the blocks is weak, you or your mechanic will need to open up the battery and test both the modules in the weak block with a multi-meter to determine which one contains the failed cell. That module would then need to be replaced, if you want to continue to use that battery. Most people would describe that as a short-term fix. If you want to use the car for many more trouble-free years, most would advise you to buy a new battery from Toyota for $2,000 or a little less, plus several hours of labor to install it. Alternatively, you could purchase a new aftermarket battery from newpriusbatteries.com, run by a member of this forum, @2k1Toaster, for around $1,600, which should have a similarly long life.

 

Leave it to a dealership to find the words "10 to 14" in the repair manual and read that as meaning "at least 14."

 

$540???
Find another dealer...

 

Thanks for updating us. It's still possible this won't turn out to be a total disaster, but having an older Prius sitting in a Toyota dealer's service bay in an inoperable condition usually doesn't end well, particularly when the information they are giving you is suspect. The 12V battery will only show a voltage of 14 when the car is in Ready mode and the small battery is being charged by the big battery or if it is actually hooked up to a charger plugged into the wall. Measuring the voltage under those circumstances is meaningless. Furthermore, in your first post dated June 21st, 2020 you stated that you already replaced the 12V battery. Was the dealer aware of that? They certainly should have been, based on the manufacture date stamped on the top of the battery. This smells of incompetence or worse. And I'm betting you paid far less than $540 for the battery when you bought it elsewhere. With those facts, I think you can play a little hardball with them. You may not think you have any leverage, but you can let them know that you will give us their name and we will help drag it through the mud. We have plenty of members in SE Pennsylvania who can help spread the message. I'm seeing 5 Toyota dealers within 10 miles of the town where you live (according to your PM), so which one of them has your car?

 

This is just a really unfortunate situation. I really thought your car would be worth saving, given that it only has 106k miles, but once you are left with replacing ECUs as a last resort, in the hope that that will solve a problem has defied diagnosis by any traditional methods, I believe that saving your car may be a lost cause. This is especially true when the ECUs are buried deep behind the dash and it seems your only possible option may be having the work done at the dealer. Even if you were to find a trustworthy independent mechanic who could do the job using salvaged parts, it would still be a major, costly undertaking.

For the record, according to Post #2 in this thread, there is no Immobilizer ECU per se, but @Patrick Wong refers to a Transponder Key ECU. I have not been able to find a reference to a Transponder Key ECU in the Repair Manual, but the first diagram I am attaching shows the Power Source Control ECU (P6) and the Certification ECU (S11). These are both behind the driver's side of the dashboard and would certainly require considerable dashboard disassembly to be accessed. The 2nd diagram shows the Gateway ECU (G1) behind the glovebox, which would appear to be more easily accessed. Possibly some combination of these ECUs performs the Immobilization function. (Hopefully, someone more knowledgeable can comment).

I am attaching these diagrams FYI, but at this point I would probably recommend getting whatever you can for the selling the most valuable parts of your car and moving on. The value you can realize is mainly dependent upon your availability of space to store a disabled vehicle and your patience. If you were to part it out, assuming the HV battery is in reasonable condition, it could be worth up to $1,000, a functional ABS actuator/accumulator is in high demand and would be worth a few hundred, the catalytic converter contains rare earth elements that are worth several hundred, and you have a brand new 12V battery. Alternatively, if the body and interior have been well cared for, the whole car could probably be sold for up to $1,500, even in non-running condition.

In closing, I am sorry for your loss, I don't know what else to say.

 

congrats!

 

Thanks for coming back to us with the good news. Only another 182k miles to catch up to our car now.

P.S. Kudos to Conicelli Toyota. Shouldn't forget to mention that.