I have an interesting problem with my truck... I have no interior lights door locks ect. I do have power seats working though with the key out of the ignition. all the above work when key is installed and put into the on position. I have checked the iod fuse and all other fuses with multi meter and dismantled the power dist point and checke d for corrosion and poor connections. I have started into the cab now tracing back towards the problem. I am now working on the instrument cluster when driving it works fine all guages work indicator lighs and so on. when I try to do a cluster code read it will not go into diagnostic mode at all i push the odometer button turn key on and nothing. if I continuse to hold the button I get the engine hour meter... I am thinking it is the module within the cluster shoted out or what have you but was wondering if anyone had another check I could try before I got too deep into this.

The truck I am working on is an 04 dodge ram 5.7 hemi 4x4 four door laramie.