Pontiac Repair: pcm trouble code 27 and 28, solid state relay, control circuits

Question
95 grand am,2.3liter,auto-trans. Trouble code 27 and 28. something about quad driver module fault. Do I need a pcm or something else? Thank you.

Answer
Hey Ray.
Quad driver codes are hard to find. basically what a quad driver is a solid state relay inside the computer. the quad driver fault is built in protection in the computer. the quad drivers run the different solenoids and relays on the engine and transmission. if a quad driver code sets the computer is either sencing a short or an open in one of control circuits. with out the use of a service manual you are not going to be able to find the problem with this. Yes it could be an issue withe the computer it's self but I doubt it. You could have a bad ground wire for the computer that can cause all kinds of goofy issues as well. on that car the ground wires on the lower transmission to engine attaching bolts have a tendenct to break on thes cars or corrode. good luck :}