2012 Prius V No Hazard or signal lights

Posting 7 threads on the same issue isnt going to get you any help.
Especially after you cut the wiring harness.

NEVER cut the wiring harnesses in a car without a full schematic and understanding about what is going on.

 

An issue where the hazard lights start flashing on their own, and faster as road speed increases, is a known gen 3 thing that can be stopped by disconnecting the sky-blue HZRI wire at pin 10 of the Skid ECU.

I haven't done it myself but others have. I had not looked at the connector closely enough to see that HZRI comes separately bundled as seen in the photo in #1. I'm not seeing in the photo whether there's only one sky-blue wire or which one was cut, so I have to assume the OP got it right and cut the one to pin #10. (If it were my car I'd have wanted to just extract the terminal rather than cutting the wire, but that's me. Cutting the wire works, if it's the right wire.)

That's all based on a 2010 liftback wiring diagram though. I've never confirmed all those details are the same for a 2014 v.

Cutting HZRI should not be connected to the hazards otherwise not working. If you hear the clicking sound but nothing is flashing in or outside the car, that would seem to be a problem in the flasher unit outputs or downstream.

The flasher unit connects to a blue connector with 8 positions, and is pretty high up under the left corner of the dash—again, according to a 2010 liftback diagram.

 

In the old days of no 5 volt micro voltages, amperages, and impedance tolerant 12 volt circuits and robust copper conductors, cutting, shortening or lengthening wires was no big issue.

Things have changed with the environment of ECU's and micro circuits. Cutting wires in the harness can change everything.

 

... but generally doesn't, in a car, with the possible exception of some circuits that carry communication protocols and have special considerations called out in the manual. Otherwise, the engineers do a respectable job of keeping that kind of complexity encapsulated within ECU modules so that most of the car's wiring is robust to the harsh automotive environment and to the kinds of things automotive electricians are wont to do.

Now if you're changing the lengths of circuit board traces inside of an ECU, you're on your own.

The HZRI input to the Skid ECU is a simple 12 volt signal, pulled to ground by the hazard switch. (I've never figured out why the Skid ECU wants to know when you've pushed the hazard switch, but Toyota must have thought it should know.)

The issue develops when something fails inside the ECU and bridges that pin with the adjacent "SP1" output pin, which produces a pulse with frequency proportional to road speed. Then the HZRI input ends up functioning as an output, effectively activating the hazards intermittently, and faster as road speed increases.

I've speculated that just inserting a diode in the HZRI line, rather than cutting it completely, would be a way to resolve the goofy flash issue while still allowing the Skid ECU to know when you've pushed the hazard switch (for whatever reason it wants to know that). But that is probably futile, as the internal fault would surely still be pulling the input down internally, and making the ECU think you were rhythmically pushing the hazard switch according to your road speed.

 

Still, I would never cut into the wiring harness. If one does and takes the car to a dealer, they would not work on the vehicle without replacing that section of the wiring harness.

Non OEM modifications could lead to endless billed hours of troubleshooting, even if the technician even wants to work on the vehicle.

 

Toyota sells "repair terminals" for their wire harnesses, which are pre-crimped to a length of wire, often 150 mm, sometimes longer; in the online Electrical Wiring Diagram you can pull up the part number of the proper repair terminal for a given connector pin. (The length is shown there too.) Assuming it got cut within 150 mm of the terminal, they'd be able to repair the harness by crimping on the repair terminal, which is an approved method.

I'm in favor of reversible mods, so if it were me I'd probably just have extracted pin 10 from the harness connector and taped it up. But that's me.

 

Regrettably, I've never gone and downloaded a wiring diagram for the v, and my TIS subscription isn't active at the moment, so I can't quickly go and confirm or rebut what the dealer said. Seems a little odd it would be that different from the gen 3 liftback, but that's a question the wiring diagram can answer and I can't.

Toyota Service Information and Where To Find It | PriusChat

 

Best then, to “report” your post to the moderator, let them decide where it should be. To do this, click on “Tools” button, lower left corner of post.

replicating the post elsewhere is frustrating to responders in initial thread; they put in their 2 cents, only to see Original Poster wander off to a new thread.

see your original post was in maintenance, and this one’s in technical. Either would do, but I’d say the maintenance forum is better, just seems to be the catch-all location for troubles.

Yeah maybe report, in the initial post here, see what the moderator wants to do. if there’s no responses still to the other, he’ll likely just delete it.