Aftermarket dual climate control issue.

[Doubeleive]

Any other electrical issues with the truck? I doubt it would cause such a problem but is the battery healthy? Body and engine grounds good? I know that's pretty general but if it happens with multiple (same) modules there may be something else going on.

some of the replacement dorman hvac controls just don't work right, they have there own programming function depending on the year/make/model it is used in so they have a one-size-fits-all solution. It comes with a instruction sheet and you have to press a sequence of buttons to set it for your particular vehicle