My 2004 ram 2500 dash lights, dash turn indicators, map lights and dome light are not working. The PCM (fuse box) has no corrosion and all fuses are good. All the lights work, head,running, turn, fog. C codes are:21, 23, a3 and a4. The rest of the instrument cluster works. The light switch looks new inside. I don't know what else to check. Can anyone help please?