P1860 Chevrolet -

Question

I am receiving the following codes on my son's truck:

P0740 - Torque Converter Clutch Malfunction
P0785 - Shift Timing Solenoid
P1860 - tcc pwm solenoid

I found the following video/article http://www.howstuffinmycarworks.com/GM_truck_bad_ign.html, do you think the codes on my son's truck could be caused by a malfunctioning ignition switch? If not, should I look at replacing the two solenoids or what?

Thanks for the help.
Merrick