95 voyager code questions

95 Voyager 3.3 engine 4 speed automatic 208,000 miles.
Friends vehicle, the check engine lite has come on intermitently. Checked codes are:

12- (disconnected battery) I know the battery has not been disconnected. I will try cleaning up battery cables and posts, seems like on this vehicle this needs to be done more than usual. Could this be a bad ground someplace??? This code has me stumped.

32- (2 seperate codes) Short or open in the EGR solenoid circuit. I will check the connector for looseness. Engine runs fine no problems, mpg seems to be the same.

Any ideas, thanks

Don't knock yourself out on the code 12. It will not make the check engine light come on. It means the PCM had a power interruption in the last 50 key cycles usually caused by disconnecting the battery. Since you haven't and all is running well, I wouldn't sweat it. At most check the battery as you're planning. On the rare occassion I check codes on my van it always has a code 12 and runs just fine.

Code 32 equates to a scanner code P0403. Here's the skinny: http://www.obd-codes.com/p0403