HELP!!! Dealer Couldn't find the problem, Prius DIED

did you check the main fuse on the hybrid battery? suppose you may have blown the inverter, and it's certainly worth swapping if you have another.

 

White fusible link was replaced?

That would be my first go to.

 

My 2004 Prius shut down while doing 65 on the interstate. Dashboard lit up with all kinds of symbols I had never seen. After I pulled over for a few minutes it let me start out again and I exited into an intersection. At a stoplight everything shut down. Couldn't roll up windows, no emergency flasher, couldn't even open the trunk. After causing a major traffic jam and a tow to local Toyota dealer, they found that my 12 volt battery had died which powers the main circuit board. They were surprised that it lasted 13 years.

 

The trouble shooting skill set of some techs is not the greatest. I have over 40 years in the trade - retired industrial electrician ---and I have fixed down computer controlled machines just because i could smell the burned burned part in the cabinet, while my cohorts in the shop had wasted an entire day trouble shooting the program in the laptop. I assume that Toyota has a standard trouble shooting tree- the problem is likely multiple failure points from the grounded wire and that has confused the tech, who got tired of chasing his tail- not making any money either , so he told the service writer he couldn't find the problem and he got a ticket for a car he could fix and make money on the flat rate allowance, too.

 

There should be a trouble shooting tree at Toyota TechInfo. @Elektroingenieur could check. I think you can get a 2 day subscription for $55 IIRC.

Toyota TechInfo

 

If OBD2 really doesn’t have power then it’s pretty simple diagnose as that’s a pretty simple circuit. That’s the way that you diagnose a complicated problem start with the simplest to diagnose symptom and diagnose and fix it. Now days many mechanics just seem to forget how to do this as there are so many fault finding trees.

 

Was it an actual Toyota dealer? If so, go to one who know what they're doing.

 

If not, go to a Toyota dealer that knows what they are doing!

 

Chapter 05 of Toyota’s Repair Manual has many diagnostic procedures, but each procedure begins with a Diagnostic Trouble Code (DTC) or an entry in a Problem Symptoms Table. There isn’t a single, consolidated troubleshooting tree for the entire vehicle; as @valde3 points out, it’s assumed that the technician can identify the relevant systems and symptoms and enter the correct diagnostic procedure.

$55 is the price for a two-day Professional Diagnostic subscription, which includes the Toyota Techstream diagnostic software and the ability to download ECU calibration files. If you just want to read the manuals and bulletins, it’s $15 for two days.

Another option might be the ChiltonLibrary service, which is available for free to patrons of many public libraries, including the Portland Public Library. ChiltonLibrary has most of the content from Toyota’s Repair Manual and Electrical Wiring Diagram books, though the user interface is a bit clunky.

Toyota also published the three-volume Repair Manual (RM1130U) and the Electrical Wiring Diagram (EWD599U) as printed books. At this writing, there are two sellers on eBay who have the full set, and others offering just the EWD. I’d buy at least an EWD book, if only for the convenience of being able to refer to it while working.

@valde3 makes a very good suggestion. The OBD II connector (DLC3 connector, in Toyota’s terms) is also the key to further diagnosis.

The circuit is simple, but it’s best to troubleshoot it systematically, with the EWD in front of you. Start with the SG (Signal Ground) and CG (Chassis) terminals on the DLC3 connector; these should both have resistance of 1 Ω or less to body ground. Next, working from the positive (+) terminal on the 12-volt battery towards the BAT (Battery) terminal on the DLC3 connector, check for voltage relative to body ground at each connector and fuse.

Once you have power at the DLC3 connector, move on to the Gateway ECU. Check for the expected voltage at the BATT, IG, and ACC terminals, and ground resistance to the GND terminal. Next, do the same for the Hybrid Vehicle Control ECU and the Engine Control Module (ECM).

These are the most important ECUs for diagnosis: once they have power, assuming the CAN bus wiring is intact, you can use a scan tool to read the stored DTCs. Once you have DTCs, you can use the more specific troubleshooting procedures to find and fix the remaining problems.

In addition to the EWD, the “Terminals of ECU” sections in the Repair Manual will be helpful for this process. They tell you what voltages should be present, under what conditions, and how to measure them. Unless you’re working on the high-voltage parts of the hybrid system, an inexpensive multimeter is fine, but you may find a set of back probes useful to measure voltages without disconnecting connectors.[/QUOTE]

 

I can see why a tech would run from this job- my shop charges $99-$149 diagnostic fee, so after 2 hours, the tech is on his nickel= his initial $30-60 of labor , becomes $10/hr if he plugs away all day trying to find the problem The dealer, I don't believe, can force a tech to work for free.
However, too many, failure to launch diagnostic tickets, might cost him a job or relegate him/her to a lower level of mechanic work

 

maybe sell it and buy something newer.

 

Sounds like a HORRIBALY run shop with no one who knows how to estimate a job or use published times for each step.

 

You do really need to have a wiring diagram. Without it you’re just guessing. But you can find the wiring diagram somewhere.

Check that there is power at pin 16 of OBD 2 connector. If no check that there is power at 7,5A OBD fuse. If no check from the diagram where that fuse gets it power and so on. Check that there’s a ground at pin 5 of OBD 2 connector. If no check the ground point.

Once you get the OBD2 connector working you can use it to check the codes. Or everything else might be fixed while you’re fixing that.

 

Wow. I don't want to be rude, but after reading the initial post, I wouldn't touch this car if I was a shop owner. (unless it was at a guaranteed hourly rate) There has been so much done to it, there's just no telling if it's now a single problem or multiple issues piled on top of each other.

Are you able to explain a bit more about the CAUSE section of the first post.

i decided to replace the AUX battery and I did something I guess called escaped charge to the ground

I'm not familiar with this terminology. I understand you had a long wire attached to chassis ground on one end and the other end accidently touched a positive terminal (battery terminal or the jump terminal in the engine compartment fuse box, or something else?)

 

You’re most welcome.

That’s a good plan. If you’re not familiar with Toyota’s diagrams, it might be worth $22 to buy one of the EWD books from eBay, too, so you can look through the whole thing conveniently, rather than trying to read only one section at a time online.

Yes, the locations of all the ground points and junction connectors are shown in the Electrical Wiring Diagram.

Frankly, nothing, unless you want to waste your time.

Don’t try anything. Use the right information and techniques to diagnose the problems first, so you can make the correct repair for each problem, without causing new ones.

If you have an hour, watch this YouTube video, produced by Toyota:

Don’t be put off by the old model (an original Lexus LS400) or the specific systems they use as examples, which may not interest you—the point is to study the troubleshooting techniques, which are as valuable today as when the video was produced in 1990.

I wish I could find another video in the same series, which explains more about how to use the Electrical Wiring Diagram. In case anyone remembers the one I’m talking about and might have a link to share, the video used a Camry or ES300 as the example vehicle and had several shots of the wiring harness and electrical components removed from the car and tied to a framework, but laid out in the same relative locations as they would be on the car, and one of the example problems involved dim tail lights.

 

Horrible story.

For lurkers You short the 12 volt battery out you can total a Prius. If your doing ANYTHING with the 12 volt battery disconnect the 12 volts leads from the 12 first. Do not take the ground lead off first like any other car at the very least you will have alot of sparking doing that. The Prius hates sparking and surging.

Take the red plastic cover off the 12 volt positive post on the battery. Has 2 clips pry it off. There's 2 black leads plugged into that assembly. One is a fat black wire that's the 12 volt main run to the jump points under the front hood. The other much smaller wire is a 12 volt sensing lead to the inverter. The plugs are the standard white plastic clips with release tabs. Push the release clips in and pull the cables out.
With those 2 wires unplugged the car is now basically disconnected from the battery. You can short that 12 out all day long and it wont bother the car. Then unbolt the ground lead.

Toyota gave you quick release clips. Use them. I have had my battery out a few times this disconnect system is safe and works. NO SPARKS!!!!

 

Here you go. Entire electrical diagram for your car. Grab it.

2005 Toyota Prius Electrical Wiring Diagram Service Manual | eBay


Btw, not sure why your in the Hybrid battery checking cells over this issue. This issue won't hurt that battery. Was the hybrid battery fubar before you blew the car up?

And btw, there's 2 fuses in the positive battery post assy, there's a 100 amp that's for the big main wire wire and a 5 amp for the inverter sense circuit.