Note: If you’re here to find out what P0700 and P1775 mean, because you just got these codes. PARK YOUR VEHICLE, GET IT TOWED TO A MECHANIC.
So I’m driving in to work, on a Thursday, about 3 weeks ago. Just minding my own business. About half way there, I notice that the LJ doesn’t have quite as much power from a stop as it usually does. So I’m trying to pay extra close attention when I pull out from a stop sign or traffic light trying to figure out what’s going on. Then it happens. Check Engine Light. I’m almost to work at this point, so when I get there, I pull out my OBD-II dongle, and check the codes using Torque on my android tablet. P0700, and P1775.
I’m at work now, so I do some research on these codes. P0700 is a pretty generic one. It basically says there’s a code stored in my TCM, and I should go check that. Reading online suggests that you need a special diagnostic tool for this, but I also have the P1775 code. Which I _think_ might me the TCM’s stored code. I could be wrong. It gives me a lot more information. “Solenoid Switch Valve Latched in TCC Position“. The linked article gives you some more info, but this seems relevant: “The P1775 code is set if three unsuccessful attempts are made to get into 1st gear in one given ignition start”.
Well.. that sounds like the thing that was giving me less power than expected from a start. Sigh. So I’m writing this article for one main reason. When I turned to the internet to find out what was up, I found a lot of information about checking electrical connections, reseating plugs, draining and refilling your tranamission, and finally checking for obstructed valves. And of course the logical suggestion that I get my Jeep to a mechanic to have the TCM scanned, maybe even flashed. All of this lead me to believe that this was not a huge deal, but should get looked at or my transmission will behave poorly. No one suggested that I not drive the Jeep. Sure, I could have been cautious and decided that the vehicle should be driven as little as possible, but I’m just not that guy.
I decided the right course of action was to get my Jeep home, and I’ll troubleshoot there. Checking the suggestion plugs, connections, maybe even drain out the fluids and refill. Since it was about time to do that anyway. So, I decided I’d take it easy on the drive home, and having 3 days before I had to drive it back to work again, I’d get all of the suggested troubleshooting done, and see where it gets me.
Wellllll… it got me about 3/4 of the way home, sitting on the side of the highway waiting for AAA. Sigh…. I was cruising down the highway about 10 miles from home, and suddenly it felt like I’d hit something, for about half a second. Then some of the most horrible noises I’ve ever heard from a transmission started coming out of my Jeep. I got pulled over, and shut the Jeep off. I got out, and looked underneath, not sure what I expected to find, but everything _looked_ ok. Let the jeep cool off a little, and hopped back in. Started it up, and tried to get moving. I was able to move forward, but after about 10 feet those noises came back, and forward travel got pretty hard. I found that if I babied the throttle, I could get moving. So I did that, on the shoulder of the road, until I got to the next side-street, and pulled off. After I got off of the highway, I tried a few things out. I’ve got no reverse, and forward is sketchy, as I mentioned. Called AAA, and waited. I was asble to move the Jeep across the street to where the roll-back might have a better time picking me up, and then I lost forward gears as well. Sigh…
After I got it home, I did some troubleshooting. Here’s a short video on how things were acting.
Very not good… I later drained out the fluid, and found some very pretty brass flake in my pan.. Not so pretty when you think about where the flakes came from. Sigh.. again.
So, after flushing and refilling the transmission, of course it still had the same problems. Looks like it’s time for a transmission. I did some research, and decided to get a Jasper remanufactured transmission. They’re not sexy, they’re not performance built, but they are reliable, and they’re backed by a nation wide warranty. That’s important to me.
So All that to say, don’t ignore the P1775. It’ll kill you. Or your transmission anyway. Check out the video at the top of this post if you’d like info on how to drop the transmission, prep, and install the new one.
Thanks for reading!