Error Codes when to check for them

[Shaun091382]

I just checked my truck per instructions on here by using a wire to retrieve any DTC's all i got was a code 12 which is fine but the truck has been sitting all night for about 15hrs should i have taken the truck for a drive first then check or does it matter? thanks for any help

shaun

[whatnot]

The computer only controls the transmission in 93 trucks. The pump is completely mechanical so it won't give any codes.

[Shaun091382]

So the ODBI diagnostic port wont give me any details on my tranny? what is the best course of action to take then?

[whatnot]

Yes, it should give codes for the transmission if it has any stored.