Transmission Electrical Connections

[Brad.Jones]

Okay so after Saturdays incident with the gearbox in my new sierra I finally had the motivation on Sunday to pull my good gearbox from the old blue sierra.
Once I had both on the bench I was deciding how to mark them in some way so I didn't confuse them, at the same time I was fiddling with the input shaft of the broken gearbox and it became very obvious how to tell them apart, one sounds like a rock cruncher and the other is silent.

Anyway my question is to do with the electrical connections on the transmission. The good gearbox from my blue sierra had 4 sets of wires connected.
The bad gearbox only had 3 sets connected with the 4th having been removed at some point. There are 3 connectors that are of the same type,
these are all connected the 4th connector that screws into the gearbox horizontally is the one that has been snipped.

So do i need the 4th switch or not?

I read this somewhere: the "fifth gear" switch turns the EGR off. The EGR valve sends a small amount of exhaust back into the engine. this lower the combustion tempeture and reduces NOX, a smog forming compound, but the trade off is that the engine produce less power.

So I am assuming the 4th switch that has been cut is this 5th gear switch.

[christover1]

The 1.3 box I fitted to my 1.0 Sierra had none of the wires on gear box connected.
It ran ok.
I think they are to do with pollution control and fuel economy?
I never used rev light switch either.

[Brad.Jones]

Yeah I understand that the gearbox will work regardless but all the same it would be nice to know what was what.
I know I have seen a diagram somewhere just for the life of me can't figure out when and where I saw it on the internet.
Anyway I have spliced in some new wires to the switch with the cut wires and will run them up into the engine bay just in case I decide i need it.

[christover1]

Good thinking.

I will keep an eye out for diagrams

[christover1]

http://auszookers.com/forum/viewtopic.p ... res+sierra

http://auszookers.com/forum/viewtopic.p ... res+sierra

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