tc lock-up switch

[CurtisvilleCummins]

best way to wire-up lock-up switch on an 06. thanks

 

[KSHall]

Pictures would be nice too!

 

[KSHall]

Anybody?!?!?

 

[JHenry]

Forgive my ignorance, but what is a TC lockup switch?

 

[Cummins724]

I remember browsing through the forums & ran across a post that said www.tstproducts.com has a wiring diagram showing how to wire them up. If this don't help... . try www.dieseltrans.com or 1-604-504-4002 Bill Kondolay.

 

[cerberusiam]

Forgive my ignorance, but what is a TC lockup switch?

The switch allows locking up the TC manually in all gears except first. It also allows holding lockup in OD with no downshifting.



1. Find pin #7, TC lock sense wire, in the trans controller plug. Drivers side of the trans towards the back of the VB area. The plug is vertical and points at the floorboards and has 8-10 wires. The 05 FSM list the color as YL\LB.



2. Tap this wire with a scotch lock and run to a SPST switch.



3. Wire a 33 ohm 1/2 watt resistor between the other side of switch and a ground.



4. Mount switch in convenient location. Done.





Couple of caveats. When on the switch wll kill the motor when coming to a stop. Lots of really bad sounds. Engaging the switch forces a very quick shift thru the gears ot OD with the TC locked. Use judiciously under full power as it is VERY hard on the input shaft.



Enjoy

 

[pipeguy]

Is it the same for the 2003?

 

[CurtisvilleCummins]

Thanks. just going to use it for drag racing.

 

[cerberusiam]

Thanks. just going to use it for drag racing.

Yep. Works great on the dyno and towing.

Is it the same for the 2003?

Should work the same way but I believe the wire color may be different.

 

[GECCO]

Engaging the switch forces a very quick shift thru the gears ot OD with the TC locked. Use judiciously under full power as it is VERY hard on the input shaft.

Can you clarify this a little more? Exactly what happens?

When on the switch wll kill the motor when coming to a stop.

So, does this mean it also locks up in first gear? Or does the transmission not shift down from second until after the truck stops?



If so, there is an easy fix to this. Put a normally closed relay in series with your lockup circuit. Feed the coil on the relay from the brake light circuit. This means that if you are driving with the lockup switch on, the relay interrupts the circuit (and unlocks the TC) whenever you press the brake pedal.

 

[cerberusiam]

Can you clarify this a little more? Exactly what happens?







So, does this mean it also locks up in first gear? Or does the transmission not shift down from second until after the truck stops?



If so, there is an easy fix to this. Put a normally closed relay in series with your lockup circuit. Feed the coil on the relay from the brake light circuit. This means that if you are driving with the lockup switch on, the relay interrupts the circuit (and unlocks the TC) whenever you press the brake pedal.

I think engaging the lockup pulls pressure from the governor circuit so the trans thinks it needs to shift, or something like that. Either way it forces it to shift to OD quite fast. It also won't allow a downshift out of OD with it engaged. The VB can be modified to stop this behaviour if so desired.





With the lockup engaged it won't downshift so the trans never gets to first gear when you stop. Using a relay like that is one way to mitigate the problem. The problem with this setup is as soon as you let off the brake it will go back to OD as soon as it is out of first gear, or immediately if the VB is modified.



Another way would be a relay that would open and stay open when the brake is engaged, then close when a momentary switch is pushed. Not sure such a critter exists. Essentially a relay that can be controlled by 2 different inputs.

 

[pipeguy]

Any idea that the colour is on the 03??? Anyone?