veltboy618

I'm clipping transmission wires & getting this 4L60E pigtail ready to be soldered when I noticed that I'm missing the brown wire that goes to the transmission connector (Pin "U"). I I have about 12" of the brown wire on the pigtail but I need help finding out where it goes from there. I have been searching & cant find anything! Here are a couple pictures below.

62n62

iTrader: (17)

from si2000 2006 truck with a 4l60e U at the 175 plug trans plug, brown wire 418 goes to C
2 plug hole 2 of the pcm plug

BOXCHEV

iTrader: (3)

Was actually working on my transmission connector today. My harness is originally setup for 4l80e and I now have to change it to 4l60e.

4l80e 11 wires
4l60e 13 wires

if I'm not mistaken

Spent few hours googling pinouts. After looking at pin outs and matching circuit #'s on the list for a 99-02 harness on lt1swap to match pin# for pcm connectors I came up with this real quick.

Hope it helps. If all the info I gathered is correct this should be on point.

Not sure though why your pin M is black and mine is Gray. I have two 4l60e plugs here and both pin M's are gray.

veltboy618

You were correct. I found the wire sitting to the side. I must have threw it to the side by mistake when I was doing some other stuff with the wires but it was already tagged that it needed to go to the #2 pin position on the red connector. Thanks for the reply!

veltboy618

I have 2 4L60E plugs & the wire pin at "M" is black on both. I think it all comes down to where the sensor ground is coming from. Good looking on that diagram. I wish I would have found that the hour I was searching before I made this thread. I'm going to save that in case I need it on the next build.

BOXCHEV

iTrader: (3)

Couldn't have found it cause I just made that lil diagram today lol.

Are you using the safety neutral switch on your trans?

veltboy618

Oh ok. That diagram helps a lot as far as finding out which pin/PCM the wire goes to without having to pull up the schematics & all that other stuff

Yes I'm going to use the safety switch. I was told that I only needed to use the 4 wires from the bottom plug since I plan on using the starter crank & reverse lights from my cars wiring instead of the upper connector on the switch. Can you confirm that this is true?

BOXCHEV

iTrader: (3)

Honestly have no idea, if that is true that would be great and save me the headache.

I have a 2004 5.3l
Harness that came with it was all cut up and missing majority of it.
It had a beat up neutral switch zip tied to the engine with the larger connector sticking out of it with these wires

Pin D has blk/wht wire
Pin C has pink wire
Pin B has light green wire
Pin A is not used

Pin G has drk green wire
Pin F has gray wire
Pin E has pink wire

I ended up buying a 99-02 harness and the larger connector for the neutral switch was cut off and missing. The wires left over were

PRND pin# 62 to red PCM connector its a gray wire

PRND pin# 34 to blue PCM connector its a white wire

PRND pin# 32 to blue PCM connector its a blk/wht wire

PRND pin# 72 to blue PCM connector its a yellow wire

And that's all I got.

I bought a new pig tail that's supposed to be for the neutral switch(the bigger connector)

Pin D is black wire
Pin C is brown wire
Pin B is orange wire
Pin A is white wire

Pin G is yellow wire
Pin F is green wire
Pin E is purple wire

Do you have all your wires labeled on yours cause I'm at a lost.

If you really can ditch that connector it will help me out big fking time lol.

Mike52

iTrader: (1)

Do you know the GM part number for that neutral safety switch?

Mike

BOXCHEV

iTrader: (3)

No, I just bought one off amazon.

BOXCHEV

iTrader: (3)

I bought this one.

Mike52

iTrader: (1)

Thanks BoxChev.

waxenate

iTrader: (5)

Newbie question...how many volts should I have at my trans? I checked mine and it was 10.3. Thanks

ealvarez11

i have been told by two different sources that you do no need the mlp switch but i still don't understand why or why not you actually need this or what it actually controls. can anybody help me out with this?

Andy4639

I have a 2003 ECU with 6.0 4l80e installed out of a Heavy duty truck in my 71 c-10 . I have a stand alone harness.

Can someone tell me if the transmission fluid temp can be turn off/on feature that my tuner can do.

I bought a scan gauge 2 reader and was hoping to read transmission fluid temperature but it doesn't pickup a signal from the ECU. Can this be turned on/off by the tunner?
Thanks for any info.

Jeff Smith

iTrader: (44)

good inform,,sub ed

G-Body

iTrader: (4)

You don`t Need the PRNDL switch but the PCM does use it to help driveability, and depending on the year/bodystyle of your wiring harness the power for your starter neutral safety switch passes through the upper connector if you use the truck underhood fuse center. Basically the computer uses the signal from it to determine idle rpm (park/neutral and in gear idle rpm may be different depending on the pcm programming), idle spark advance, and probably a bunch of other things. For most hotrod swaps we could eliminate it and not really notice any change. If your looking for OEM level perfect new car idle quality it wouldn`t hurt to keep it. I usually keep it if possible or switch to a P/N switch that gives the same function to the PCM. If you are going to get rid of it, just ask whoever tunes your pcm to set the PRNDL switch to NONE in the pcm.

G-Body

iTrader: (4)

The warning "check engine" light for a transmission fluid overtemp would be easy to turn off with a tuner, but to turn off the actual ability for the pcm to monitor the transmission temperature would be very difficult. I don`t believe any of the standard tuning software offers that option. You would have to hack the computer code yourself. Can you plug into your obdii port with any other type of code reader to check it? HPTuners, EFILive7, autotap, tech2? You could also try testing your transmission fluid temp sensor with a ohmmeter to see if its working.

Jeff Payne

The plug coming off of the trans has two pink wires and two yellow and black wires and a white wire that I need to figure out where to connect them. The wires were cut.
On the trans plug "B" and "L" are both yellow and black. The plug on the other end of the harness has a yellow and black in the "C" and "M" plugs.

The trans plug has a pink wire in the "E" and "N". The plug on the other end of harness has a pink wire in "D" Does one go to a power source?

I hope I am making sense. ANyone have a good diagram of the trans plug and the harness?

Thanks

BOXCHEV

iTrader: (3)

Did you see the pic in post #3?