P0705 Park Neutral Switch

You are one of the most recent post and my 2007 Tacoma just started doing this. Have you found a fix yet?

 

Has anyone had sporadic acceleration with the PO705? I have had it a couple of times going 15-25mph, it feels like i am pushing the has real hard a couple of times combined with slipping in the tranny. I assume this is related to the Neutral Safety Switch needing replaced or cleaned.

 

When your computer sees an issue with the switch or the wiring , the computer triggers code P0705 which puts the transmission into limp mode .
Depending on the gear range the computer doesnt see , it may select 3rd gear . Taking off from 3rd gear at a set of traffic lights isnt great for the transmission and may be what you are feeling . Because limp mode was designed to limp your truck to a shop to get the issue repaired , its highly suggested that you try and fix up the issue quickly .

 

Thanks for the helpful info! Fortunately, I do have a beater car that I am driving until I get the issue resolved.

 

For what it's worth, we went on vacation for 2 weeks and came back after last week's storms. We didn't get floods, but we did get 6"+ of rain in a few hours.

Took the Tacoma (2005, 215000 miles) on Thursday and thought the shifter felt tight. Really noticed it on Friday, at which time it threw a P0705 and I noticed the "2" flickering on the display while in "D".

On Saturday, it got even stiffer, and I started seeing "R" & "2" simultaneously when in reverse. Then the shifter loosened back to normal, and I had "P & R" when in reverse and "R & D" when in drive.

Ran it to the mechanic yesterday. The switch was corroded so badly that they had to pry it off the shift linkage shaft in pieces. Still, better a $300 switch than a $1000 harness.

 

Both. It was physically hard to pull the shift lever back into gear - (quite stiff feeling), and it wouldn't go into gear until the appropriate light (D) illuminated in the dash - this required some wiggling and back and fourth of the shift lever. It was even more difficult to get the shift lever into the lower gears.

It's currently working great. My experience (currently at 281,000 miles) is that it is an intermittent issue that comes and goes with months or even years between occurrences.

 

Gunn

Gunny’s price for the switch is $218 shipped.

I was thinking of buying and installing it, but my tight shift lever feel and P0705 code has never come back after I cleaned the DS kick panel Junction box connector with electronic cleaner and sealed it with dielectric grease.

 

2005 Tacoma, 4x4, V6, 190K miles.

Symptoms started shortly after I had the frame replaced as part of the corrosion recall, although I'm sure they are unrelated.

1. Hard to shift from P into any other gear. Got worse over a few days. Hard gear changes.
2. One day truck wouldn't start: Check Engine, Batt, and "AT OIL TEMP" illuminated. Also, P0705.

Read through forum posts and did the following:
1. Cleaned all mentioned connectors (kick panel, PN switch, etc). I did not see any corrosion or water in the connectors or coming down the harness from the firewall.
-no luck
2. Replaced PN Switch (~$230).
-no luck
3. Completely disassembled, cleaned and greased the shift mechanism (out of desperation).
no luck

Currently the shift mechanism, cable, PN switch are all lubricated and functioning smoothly. The only "abnormals" are the Check Engine, Batt, and "AT OIL TEMP", P0705 and the absence of the N when I shift to the neutral position - I don't know why.

I haven't been able to start the truck since August; the work I've done so far was done on my limited free time. It seems the next step is to take it to the dealer for the dreaded $2K+ wire harness replacement, unless anyone has another tip. Budget isn't really there for a dealer fix.

Thanks for posting, everyone.

 

The absence of the neutral light is the key here .
Either the new PN switch is faulty or the wiring going to the nuetral circuit is faulty .
Once the code goes away , everything will go back to normal on the dash and no more harsh shifts . If I had to guess , wires were tugged during your frame replacement .
You could always go back to Toyota and say its been like this since you swapped out the frame and request they check the wiring or continue on your mission trying to find the tugged out wire .
http://www.customtacos.com/tech.old...06toyrm/06toypdf/06rmsrc/rm2006ta/0270013.pdf

Do you have a DVOM meter ? Follow the schematic at the above link for the neutral circuit and you will find the problem


Rostra also makes the switch

http://www.rostrapowertrain.com/typ...a&transmissiontypes=a750e-5-spd-rwd-2003-2016


And the internal / external harness

http://www.rostrapowertrain.com/typ...a&transmissiontypes=a750e-5-spd-rwd-2003-2016

 

Gearcruncher, thanks for the post. While I certainly hope the OEM replacement switch I got for $200+ isn't defective, I'll consider it a variable in what I do next: tracking down the bad wire. I've got a volt meter and will start with the wiring diagram you linked to (thanks). It may take some time but I will report back with findings and some pictures; I'm sure there are others with the same problem reading this.

 

Let me know if you fix this, I pulled a wire out on mine, got a new connector with the wiring and spliced it on and my truck won’t start. Before the neutral light was out, but after splicing the new one on, the neutral light is back on and the park light is out. Truck still won’t start though.

 

Just got this today after a HG replacement. Can this be repaired by dealer easily?

 

Did you do the head gasket repair or was it done by a shop .
Its a busy circuit with a lot of wires and can be time consuming to diagnose $$$$$$
If they removed a bunch of wiring to repair the head gasket , chances are its the reason your code is popping up .
Try clearing the code , then check for codes again to see if it went away .
Sometimes guys forget to remove the battery posts and start removing wiring while the key is on .
leaving the battery connected while removing wiring will set codes

 

Thanks for the info. Yeah I'm here at the dealership. Suddenly an abs sensor went off too. So it's either they moved a bunch of stuff and triggered it or battery is below voltage. The entire engine was pulled, so the harness was moved and adjusted alot I presume.

I just hope they take responsibility. Just had the HG replaced and within 30 miles 2 codes thrown.

 

So I guess the shiftscable is binding and rusted. P/N 33820-04010.

 

Was the shifter cable hard to move before you had the head gasket replaced ?
I am not saying the dealership rusted the shifter cable for you , but its really strange that you didnt have an issue before the head gasket was replaced ?
Now you have to pay for a shifter cable $$$$ .
I would be asking to see this rusted cable and why is it binding ? did somebody forget to disconnect it while removing the engine ?

They are called stealerships for a reason . You just dropped big bucks on a head gasket job and now they want you to eat a mistake by paying for a cable ?

 

Yeah no issues before this. I hear what you're saying. Notably when I picked it up shifter was working perfectly again. They said they could spray it with a little lube under the cab, and they must have. No issues now. Check engine code cleared. They also said abs was a pending code. May be from 6 months ago when I replaced the abs wire. But I have the part number at least if I need to fix it. Doesn't look too bad to do.

 

Ahh well .
Keep an eye on it . I think you have 30 days after the job was performed to bring it back for issues .
I have a bunch of info regarding the shifter cable as well as your code within my write up that you can read when you have time .
Maybe I was jumping to conclusions a little too quick as it sounds like they fixed you up

https://www.tacomaworld.com/threads...th-pics-for-second-gen-4-liter-trucks.289913/

 

Thank you. They actually gave me an estimate ($800) and wanted to replace it but fortunately they didn't have the part in stock. Glad the tech got it working again, though jury still out on who caused it.

 

Haven't had a chance to work on the problem for a couple of months. Life. Today, with a charged battery, new P/N switch and renewed motivation I did this.

I was able to do some voltage testing on the SHIFT LOCK CONTROL SUB-ASSEMBLY (the shifter) using the "SHIFT LOCK SYSTEM ON-VEHICLE INSPECTION AT-148". Either I don't know how to do this right (very possible), or the ECU is shot: there was no voltage reading on any of the terminals. Before I look around for a replacement ECU sub-assembly I need to ask for assurance that I measured the voltage correctly.

I selected "DCV" on my volt meter, inserted the the black probe pin into Terminal 8 (E) and the other red probe into 1 (KLS+), 4 (ACC), 9(STP), and 5 (IG). The connector was still connected and I inserted the pins where the wires feed into the plastic connector. I induced the listed measuring conditions and none of them showed any increase in voltage. I stopped there to come in and write this so I don't go down the wrong rabbit hole. Can any of you offer advice for a novice like me on whether I'm doing this right.

The next step is to look for a new ECU sub assembly. From the looks of it, the entire shift mechanism (UNIT ASSEMBLY, SHIFT LOCK CONTROL (3356004010)) costs almost $600. I'll look around from just the circuit board.

Again, reading the threads, it looks like the dealer wants $2-3K for this repair. Don't have that money, but getting a bit desperate.

Thanks again for all the inputs.