Car is in limp mode and seems the transmission has partially gone out?

Good morning, KIWASABI1,

While looking at a wiring diagram for your vehicle I noticed that the Output Shaft Speed Sensor, Input Speed Sensor and the Park Neutral Position Switch all share one wire in particular. A black wire with an orange tracer/stripe. Then when I read you have nothing on the dash telling you what PRND mode you are in I was thinking more the PNP switch.

So, it may be the harness itself or the Park Neutral Position Switch. Both are very likely. A shorted harness should blow the fuse so I would start by checking the fuse with a test light. It should be fuse #5 will be a red 10 AMP. This panel is located in the passenger compartment on the left side of the dash.

Since you mentioned that you think reverse hasn't been showing up for a while that may have been this PNP switch going. So next I would unplug the PNP switch. It is right on the transmission. I have included a diagnostic chart for this switch. I would chock the tires, so it doesn't roll on you and test continuity in each shift position. Do this with the switch unplugged instead of back probing the connector because a continuity test induces a voltage and can short things out like the PCM. You will also need a Digital Volt Ohm Meter to conduct this test. If you don't have one, you can find it at your local auto parts store. I will add a picture of this tool for you.

If the switch passes, I would check the harness starting at the transmission and work your way to the fuse box. Be sure to check especially where it would contact the transmission or engine where it could rub through, any splices, and all connectors.

Let me know if you find anything. Also let me know if you need any guidance on these tests. Hopefully it is just the PNP switch since it is a high wear point because it is used constantly to control the movement of the car.

Here are a few articles that will help:
https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

Thank you,
Brendon

Hello KIWASABI1,

You are very welcome. Neutral Safety Switch might be built into this, but another name would be Range Switch. Some vehicles have a range switch on the transmission and the Neutral safety switch is built into the shifter itself. I found one on RockAuto for you I will add a couple of images for you.

Their part number is 1S5697.
I have never purchased this brand before so I can't speak on their behalf. It does come with a 3 year/36,000-mile warranty though. Price is $57.59 plus tax and shipping.

This is the Mitsubishi part number I found 8604A011
This is the part number my tech reference is giving me so it may not be up to date. If you want to go with Mitsubishi, I would call your local dealer and give them your VIN number. My information is telling me this part is around $103.00.

An electrical issue would make sense because like you said you can still drive it.

Thank you,
Brendon

Hello KIWASABI1,

I would say it is an easy-moderate job. The biggest thing is making sure it is lined up. I would use a sharpie and mark as much as you can like bolt positions and maybe even trace around it if you can, so it lines up perfectly. I am adding the removal and installation procedure for you that should help as well as torque specs.

It is your choice, but I strongly advise doing some testing on it first before replacing it and I would definitely stay away from Duralast. Their parts have always given me nothing but issues but that is your choice as well. I recommend going to NAPA or the dealer. Dorman has come a long way and would be a good choice as well. The last thing you want is issues and have to replace the part again or it not actually be the issue and waste your money. Just my advice. Trying to help the best I can.

It might be a good idea to use some blue thread lock on the mounting bolts, so nothing loosens up on you down the road.

* Note the torque specs that are given are in inch pounds. *

Good luck and let me know how it goes. Also, I don't know if you celebrate Easter but if you do have a Happy Easter.

Thank you,
Brendon

Good morning, KIWASABI1,

Well, that's good, I am glad you were able to drive it, and everything worked fine for at least a little while.

All 3 of these codes are for a short circuit or open for 3 different sensors that share a single wire that goes to a fuse that is blown.

It is definitely possible the switch is shorting out internally or has excessive resistance. Then popped the fuse and since that same fuse gives power to the other 2 sensors you have codes for, the PCM set codes for all 3 components in the circuit since all 3 now have no power.

I just wanted you to test the switch to see if there was any excessive resistance in any position, so we knew for sure it was that part causing the issue, so you didn't buy something you didn't need. Since like I said is a high wear point it is very likely it is that, but just because it is likely does not necessarily mean it's the actual problem.

Since you already bought the part though, put it in and see what happens. If the problem still exists, we will know it's not the switch and will have to look further. If the problem doesn't return, then awesome. You will be all fixed up and ready to go.

Let me know how it goes or if you need any additional help with installation.

Thank you,
Brendon

Hello KIWASABI1,

Not to worry, I was wondering what happened to you. I figured you got it all fixed up. Glad you found the issue though. A lot of people don't think about things like that and just replace things. Happy to hear you were one of the other ones and found and solved the actual problem.

Wiring issues take a lot of work to find and even a lot of Technicians can't fix them. So awesome to hear you got it!

You are very welcome though and I am happy to hear I helped you out.

If you need anything else let me know or just start a new question.

I hope you have a great rest of your week!

Thank you,
Brendon