View Full Version : 04 2wd Silverado wire diagram


76LQ9TA
11-20-2006, 10:05 AM
Does anyone have a picture of the wire diagram for the Park Neutral Position switch for the 4L80E transmission for the 2wd truck? I need to connect this to the 4L60E harness I have. This is the vehicle the trans I bought is out of. The diagram I need is for the grey rectangular connector with 9 or 10 wires going to it.

Thanks

'JustDreamin'
11-20-2006, 08:33 PM
Hey Boss....

I've got some recent experience with that.

Easiest solution is to buy a new range selector switch that matches the harness. I just went through this with my '04 80E. Bought a switch for an '03 80E and it plugs in (2 different connectors vs 1 connector). Cost on the range switch was like $35 and my local dealer had it in stock. I have no idea what the part number is. But changing the switch to match the harness should be a whole lot easier than re-pinning it, especially at the cost of a new one.

Also, be warned that the big round grey connector on the 80E and 60E pin out differently. There are a 3 wires that are different. 1 controls the TCC lockup solenoid, and is in the wrong spot. The other 2 need to be used for the Input Shaft Speed Sensor. You'll have to pull them out of the big grey connector and hook them up to a connector for the ISS. You'll also have to move the PCM ends. I still need to do this on my truck. Seems to run ok without the ISS, so you might could have it deleted. Not sure of the potential downfalls are of deleting the ISS.

Off the top of my head, I don't remember which wires move.

'JustDreamin'

76LQ9TA
11-21-2006, 08:06 AM
I have the switch from the 4L60E trans. So they are interchangable? I was going to run the second VSS to the PCM. I don't think there are currently pins in those locations. I know about switching the 2 wires on the circle connector. I thought I would not use the other two on the 4L60E that aren't on the 4L80E connector. I guess I've got some more homework to do. The dealer faxed me a schematic for the 4L80E trans but the wire colors aren't matching what I see on the harness. That is why I started this thread. Do you know the part number for the pins in the PCM. I have to buy one to control the electric fans. Thanks for your help.

'JustDreamin'
11-21-2006, 11:52 AM
I have the switch from the 4L60E trans. So they are interchangable? I was going to run the second VSS to the PCM. I don't think there are currently pins in those locations. I know about switching the 2 wires on the circle connector. I thought I would not use the other two on the 4L60E that aren't on the 4L80E connector. I guess I've got some more homework to do. The dealer faxed me a schematic for the 4L80E trans but the wire colors aren't matching what I see on the harness. That is why I started this thread. Do you know the part number for the pins in the PCM. I have to buy one to control the electric fans. Thanks for your help.
I believe the 60E and 80E switches are interchangeable, but I would have your local dealer verify that.

There are 3 wires in the circle connector. If I remember correctly, you need to move the wire from pin U to pin S. Pin T is not used for the 80E, and the wire that came out of Pin S isn't used either, meaning you have 2 extra wires already in the harness. Those 2 wires already terminate at the PCM, but go to the wrong spots. I think they both need to be in the Blue connector for the ISS, but 1 is in blue, the other in red.

Don't have any clue what the pin part numbers are. Jarred @ Current Performance Wiring (S10 wiring harness specialist) made my harness up, so I didn't have to buy any of those bits and pieces. Maybe somebody else on here knows the part number for the pins.

And that Second VSS as you called it is measuring input shaft speed, so that the trans controller can detect clutchpack slippage (by comparing ISS reading with VSS x gear ratio) and TCC slippage (by comparing crank sensor to ISS).

'JustDreamin'