P lock error received while going 70 on the freeway! how to fix?

Hey guys,

I have a 2011 Prius with 180k miles on it. I think it's tired of my abuse and it trying to die on me but I'd like to keep it going, especially right now with car prices all out of wack.

a little history on the car in case anything done to the car could hint to a possible solution... I couple months ago I took it to the dealership and they replaced the brake actuator and accumulator under the extended program that has been discussed on here before. At the time I also started having the misfire on cylinder one code. after swapping the spark plugs and coils from cylinder one to another cylinder I was still getting the same code so I took apart and cleaned the egr, throttle body, and intake, replaced the sparkplugs, hoping that it wasn't a blown head gasket. that didn't work so I ended up replacing the head gasket. I followed procedures I had seen on youtube videos, where you pull the intake, disconnect all the electrical and just move all the electrical connections to the right side, etc, etc. I got it all back together and it seemed to work fine for a week or so, but I had only driven it 2 or 3 times for short distances. at that time I also replaced the PCV valve, coils.

The morning of the issue I went to the convenient store and on the way home it was running rough, a code indicated an issue with coil on cylinder 3. I bought toyota coils on ebay and remembered that coil looked like the factory box had been opened before, anyway, I put one of the old coils back on and the engine sounded good and no more code.

then I left the house for a 40 mile trip each way. I was driving on the freeway about 25 miles into the trip going about 70ish when the alarm sound went off and the P lock malfunction warning came on and my car just coasted. I've read many threads where people have had issues but most of them involve a parked car. Anyway, I coasted it to the shoulder and tried pressing the park button but it didn't do anything so I left the parking brake on and got a ride to a work inspection. I messed with the power button until it seemed like I turned off the car before I left. I left the car thinking it was in neutral but I guess when I turned the car off it must have engaged the parking pawl because when I met the tow truck driver there to tow it home the car was stuck in park, even though it was still giving the P lock error and the light on the parking button doesn't light up. it's like the car doesn't know it's in park.

my battery is a 4 yr old optima. I checked the voltage to the battery at the fuse box in the engine compartment and it was 12.6v, turned on the car and it dropped to 11.9v. I checked the p-con fuse and it was ok. I did find that a 20amp IG2 fuse was blown and I replaced that. I've left the battery unplugged overnight hoping to reset the code and hoping that would work but I still get the code.

I got the vxdiag thing off amazon and put the software on an old computer cause I read there were viruses on the program. it gave me a C2309 code. clicking on the snowflake gave me the info seen in the pics.



Any ideas on what I should look at next?

thanks
jeff

 

Thought my battery was fine but a lot of threads talk about getting a new battery so I tried that. Didn't work.
.
Transmission control unit maybe?

SM-G998U ?

 

Thanks for the reply!!
I turned the car on and pulled the fuse and checked each terminal against ground to see what the voltage was and I got none on either side. wasn't sure if I should try across the terminals so I did. zero as well.

it looks like the gray block next to the spare fuses is labels IGCT so I assume that's the IGCT relay? i'm not sure how to remove or how to test voltage there. if I can remove it I assume i'd just check voltage of each terminal to ground, yes?

thanks again!
jeff

 

I pulled the relay and with power on I got 11v at this terminal

SM-G998U ?

 

12.4v with power off, 11.77v with power on.

SM-G998U ?

 

the diagram makes sense to me but i'm not sure about the numbers. on my photo, the upper location provides 11v when the key is on and the connector the opposite is grounded so I assume that's 1 and 2 and with the key on it should power the coil closing the relay and letting the power or signal flow through 3 and 5, but that's about all I think I understand. sorry.

 

Ok chap and bisco,

I'm an idiot. I was looking at chap's diagram and thinking well, the relay should kick on and let power flow through but I didn't get power from either terminal of the 10amp igct fuse. looking at the diagram it seemed like power came from the igct fuse and that looked like it might be the 30amp fuse in the fuse panel, but I checked them all. So I decided to see if I had voltage to that fuse and that's when I figured out that I put the fuse back in the wrong spot and put it in where the 30amp fuse would be for an amp? i think. anyway, I put the 30amp fuse in the correct spot and put the 10amp fuse back in, powered it up and the light on the parking button lit up. closed the hood and put it in drive and drove forward a few feet and then put in park. it works!!

not exactly sure what happened. the only thing I found wrong was the 20amp IG2 fuse blown. maybe the change in battery? i'm not sure. but it works now, we'll see how it does after a longer drive.

thanks guys
jeff

 

OK, so I took it for a drive today or I drive today or should I say I tried to take it for a drive. I got towards the end of the block and blue the 20 amp ig2 fuse. The p lock malfunction went off since I was moving at the time but once I came to a stop I was able to replace the fuse and it was and drive home.

So I think I have ig2 issue and not a p lock

SM-G998U ?

 

I hadn't downloaded the wiring diagram yet. I pulled the car in the driveway to take a look and while running it blew the IG2 fuse again. I looked at the wiring to the coils and injectors and other wires I moved when I pulled the head and didn't see anything obvious. I decided to put the other three old coils back in since I had a problem with one of the new coils previously and I never had a prob with the old coils, I just replaced them because I had access. anyway, I drove around the block with no issue. just drove 40 miles with no issues. Hoping it was as easy as a bad coil. I will drive a 3 hr trip on Sunday so we'll see how that goes.

jeff

 

Well, drove 165miles from Long Beach to Bakersfield without issue. So, definitely not a glowing endorsement for eBay coils. Oh well, just happy to have it back on the road.

SM-G998U ?