J12 plug on mfc-01

[trucklover]

Hey guys. I read somewhere on this forum that if you cut and strip the green and black wire (j12) and connect them together, you can increase the power output of your truck while getting rid of the coupling sound of the 5th wheel. Is this correct? Would you be doing any damage to the mfc-01 if these wires are connected? Thanks as always.

[mavrick0]

No damage all it does is put the truck into a "towing" mode and always thinking it has a trailer on and the MFC put out more. A lot of guys do it. You just loose the coupling noise if you do remote coupling and uncoupling.

[ricm]

Yeah it's a safe mod. But I think 'towing mode' only increases power for 1st gear, so motor power is not affected by connecting J12 pins together for 2nd and 3rd gears.

[trucklover]

So I can join the two wires, but do I have to put anything in the J12 socket? Thanks for the info.

[ricm]

take the coupler switch lead with MFU connector on the end.

cut off the switch.

solder the green and black wires together on the side with the connector, remember to insulate the join properly. best way is to use heat shrink tubing.

plug the connector back into the MFU, so that the MFU pins for J12 are now shorted together. This simulates the condition with the coupler switch closed, which happens when a trailer is connected. The MFU will deliver power to the motor accordingly.

[trucklover]

Thanks for your help. Will get on that this weekend.

[ricm]

keep the switch, somebody might want it!