Recent content by Ed Driscoll

Tmax has manual override via pushbutton on the unit and emergency override. When main dead the controller will Only show auxiliary lights, if you look closely you will see I added diodes to allow override with whatever battery is still live. Note flyback diode in the schematic as well, for...

Repair info for T-Max DBS02 PCB, my schematic dual battery 2013 Sierra GMC TMAX DBS02 PCB by Ed Driscoll posted Aug 25, 2017 at 1:36 PM

During the install I managed to Blow the output Transistor in my Tmax Dual Battery controller. You accomplish this by shorting the green wire from the controller to ground while powered. Here are my uploads of the original install and the PCB repair and part #'s etc...

Great Write Up ! If you accidently short the green wire out of control module to 0volt ground , trying emergency override or testing your new install, trying to get coil to pull in, you will destroy the Mosfet output. Typical symptom is the control module always has the solenoid on as soon as...