This made no sense. When I get these done, I'm back on my 450s, you'll hear from me again.

 

Good to see you back here. I wondered where you went recently and hoped that everything was alright.

I did notice the wiring diagram this morning. Please keep us posted with your diagnostics results.

Rob

 

I'm making progress - mostly by finally securing a complete wiring diagram. Y'all know I hate electronics. Basically spent most of the day reading this diagram, lol. Mostly fine. Still miss my dog...and my life. This new one sucks. Dad's on his last legs. I gotta get all this work done before I'm too old to do it, which I already am. But no one else to do it, lol.

I still got my trucks to work through. I got my F450 looking good, and the numbers seem right, but it just doesn't seem right, and I smell exhaust in the cab. So I gotta get back on that when I get rid of these Prii.

 

Well, I'm stuck on this car. I know y'all can't diagnose, but maybe y'all have some good advice on where/how I go from here. This car has an intermittent electrical issue. It was in a wreck of the passenger side doors (sedan), which I expect caused the problem. I jumped it at the auction and drove it home, no problem. In fact, it drove so well that I decided to fix it rather than use it for parts (extremely low mile car). Later, I noticed that when I started it, the key at ACC did nothing, the entire car dead, but it would still start and everything (dash lights/gauges/acc) would instantly work just fine.

Then, it wouldn't start. But if I unplugged the battery (I assumed to clear codes - can't get TP to connect to these cars) and let it sit awhile, it would start and run just fine.

I've checked all the fuses, and swapped all the relays with one of my running cars just like it, and both cars didn't change. I've pored over the wiring diagrams looking for common connections to what's not working (everything) and the impact area of the wreck. Spotted a possible grounding point, but it looked fine. Reset it anyway.

Yesterday, I thought I made progress. Since TP issues, I borrowed a cheap plug-in scanner to read codes. It only displayed 2 from the ABS module, which kinda didn't make sense. I tried to clear them to start over, and the CELs stayed on. I drilled into the device, and it lets you clear codes by module or all-of-the-above. This time I went module by module and the lights went out on the Engine module. IDK what that means exactly. Those are the device's terms.

Still, after that, the car began starting consistently. It still was dead at ACC, but was back to starting in ON. Before, when I reset by discoing the battery, it would go dead again after a few test starts or if let idling for 20mins or so. After clearing the unknown codes in the "Engine" module, it quit doing that. I started it prolly 10x yesterday trying to get it to fail. Drove around my neighborhood, off the busy streets a couple of times for a couple of miles each time. Never failed, ran fine, still flaky with key in ACC

But doncha know, at the end of the day, I thought I'd go get some gas for it, almost empty, got on the busy road for the mile drive, and it does the flickering lights/display thing and dies. I disco the battery about 20 minutes, start it again, normal for about a 100 yards, then dies. 20 minutes another 100 yards. Pulled it home and not sure what do look at.

What do y'all think about the way it runs fine, all the lights/acc/engine, when it runs? Doesn't that kinda eliminate a bunch of problems deep into the wiring diagram in favor of a higher-level issue? I get an image of something heating up and shutting off, then cooling off and working again. Are there components that act like that? Am I looking for a bare metal short, a bad ground, a burnt ECU, a loose connection?

The way the symptoms change is maddening. Before, I'd notice that after turning it off the Door Ajar lamp stayed lit, albeit dimly. Last night, the headight on dash lamp stayed on. When dead, some fuses display 0.0v, other times Innova doesn't sense them at all, other times they're 3.9v, and if it's acting dead, those fuses drop to 2v when you try to start it.

Maybe y'all can't say because it could be any of those things. If so, I'm stuck and will have to take it to a tech. But of all the techs, wiring guys are scariest to me. I have no way to know what they're telling me is true. Maybe y'all have some advice on anything I can do/learn to protect myself before I take it to them.

 

Any way to swap the ECU out with a known good spare, or does that lend to other issues with security and keys etc. I don’t know much about the hybrids, but it’s gotta have a rather robust control system. Like it’s running on gas, but switches to battery and dies. Is that a thing? Can you you only select gas mode?

 

Thanks Chuck. I have spare ECUs, but had the same concerns about the immobilizer system. I've swapped one of the "sub-ECUs" that controls the dash that's not lighting.

It is "robust," kinda like the way Micheal Corleone had a "buffer." Basically two engines in one car. No starter, no alternator. Can't select gas mode - the electric engine is what starts the gas engine - on and off while driving.

I think that if I can find the parasitic drain, I can live with the ACC mode not working. That drain kills my battery pretty fast. I've been reading up on how to do that. If I'm lucky, I've got a bad circuit running something I can do without, like a power window or door lock.

I hate taking a car to a tech when I don't know what's wrong with it or, worse, when I still wouldn't know what's wrong with it after he told me. I'm in "muffler bearing" territory on electrical problems.

 

Don’t sell yourself short. The same basic troubleshooting method works for mechanical stuff as it does electrical, for the most part. It’s a matter of breaking down the problems into smaller sections and narrowing them down to circuits or components. Knowing what each device or subsystem is supposed to do is key to figuring out the issue. What are you missing? Then go after that to figure out why. Same as the 6.0. It’s a complicated system, but when you break each component down and figure out what it’s supposed to be providing you can figure out what’s not working. You can do it…..(my best Rob Schneider impression)

 

If I thought anyone would pay for my shortness...

I expect I could have done this - 20 years ago. The old gray mare just ain't what she used to be, lol. However, I expect I will do this, lol, I don't have much choice. Gotta get these cars gone. Can't retire until I do. The fun one is gonna be this ambulance in my back yard. The one that ran fine until I swapped in a new oil cooler and it never started again. I'm down to just three Prii ahead of it.

Another Prius I'm working on now - when I get pissed at this one - has AC issues, which is the other car tech I'm not good with. Nuts, bolts, wrenches, I can do that. If it takes knowledge, I come up short a lot.