Trucks Got Problems! Looking Under Hood And Found This. WTF!

[Blown06]

I'm looking around under the hood tonight wondering why my truck sucks and I found this connector unplugged. I don't have a clue what it is or why it was unplugged. It looks like it connects two harnesses together. One end goes into the loom that goes toward the back of the truck down the frame rail. Anyway, I plugged it back in and the truck still has issues, but what I'm wondering is what was not working while this was unplugged? No telling how long its been like that either. I don't ever remember unplugging it and it snaps together tight. The plug is located between the fuse box and the firewall down by where the harness goes into the fuse box. Here are some pics. Can anyone tell me what these wires are for?

[RedHeartbeat]

The V-TAK module!

[Blown06]

hmmm....I don't get it???? V-TAK???

[DUMPD04]

think he was joking and was talking about vtech? thats what i got out of it! dunno what that ones for...i know a few of mine came undone one time and cruise control stopped working and the tach would tweak out sometime...hope yours is nothing critical tho

[RedHeartbeat]

Urban Dictionary: vtak

[ChubbyBuddy]

looks like a wideband plugin

[farmtruc]

Looks like the Generator Battery Control Module plug.

I'm not gonna act like I know exactly what it does and explain, so here's the GM description:

Starter/Generator Control Module

The starter generator control module (SGCM) controls the flow of torque/energy into and out of the starter/generator. Overall, the SGCM controls the starter generator's engine cranking, torque control, speed control and torque smoothing/active damping functions. The SGCM also controls the four types of power:

• Perform bi-directional 36-volt DC to 12-volt DC electrical energy conversion between the 36-volt DC bus and the 12-volt DC bus for system energy management.

• Perform bi-directional DC/AC electrical energy conversion between the 36-volt DC bus and the 3-phase asynchronous machine

• Provide 120-volt 60Hz AC energy for on and off board electrical equipment.

• 28-volt AC for the starting function.

In the basic, 3-phase inversion/conversion process, 42-volt DC is converted to AC for starting, and, conversely, AC is converted to 42-volt DC for recharging. In addition, 14-volt power is converted to 42-volt for jump-starting, 42-volt power is converted to 14-volt for the battery charging function, and 42-volt power is converted to 120 volts AC for powering the auxiliary power outlets.
The SGCM has two discrete crank signal circuits inputs to calculate engine position. One is hard wired and one is a signal on the GMLAN bus. This acts as a back-up system in the event that one signal is interrupted the engine will be able to start and run although a DTC will set.

[yournamehere018]

Looks like the Generator Battery Control Module plug.

I'm not gonna act like I know exactly what it does and explain, so here's the GM description:

Starter/Generator Control Module

The starter generator control module (SGCM) controls the flow of torque/energy into and out of the starter/generator. Overall, the SGCM controls the starter generator's engine cranking, torque control, speed control and torque smoothing/active damping functions. The SGCM also controls the four types of power:

• Perform bi-directional 36-volt DC to 12-volt DC electrical energy conversion between the 36-volt DC bus and the 12-volt DC bus for system energy management.

• Perform bi-directional DC/AC electrical energy conversion between the 36-volt DC bus and the 3-phase asynchronous machine

• Provide 120-volt 60Hz AC energy for on and off board electrical equipment.

• 28-volt AC for the starting function.

In the basic, 3-phase inversion/conversion process, 42-volt DC is converted to AC for starting, and, conversely, AC is converted to 42-volt DC for recharging. In addition, 14-volt power is converted to 42-volt for jump-starting, 42-volt power is converted to 14-volt for the battery charging function, and 42-volt power is converted to 120 volts AC for powering the auxiliary power outlets.
The SGCM has two discrete crank signal circuits inputs to calculate engine position. One is hard wired and one is a signal on the GMLAN bus. This acts as a back-up system in the event that one signal is interrupted the engine will be able to start and run although a DTC will set.

Is it a hybrid?

[cjriojas]

well in short, it connects the voltage changer to the stuff that needs the voltage changed.