Guys, a do-it-yourselfer needs your help. 2003 2500 4x4, pretty stock, no chips ect.
Started a few weeks ago with unusual dash cluster malfunction. Checked connections and tightened the ground behind the ECM and it was fine after. Then started having a parasitic amp draw. Bith batteries tested by Napa in February, one fine, one replaceed under warranty.
So, amp meter between pos cable and pos post, secondary batt disconnected. Draw was fluxing between 1.8 and 2.5 ish amps, removing either fuse 11 or 13 brings it down to .8 amps then it drops to millis. Both fuses say FCM power supply.
Also the odd thing, reinstall the fuse and it stays at .8 amps untill i contact pos cable to pos post again, then the wild fluxing begins again.
Turn signals and hazzard lights off too!
WHAT THE ??????
any advice on anything i can test or look at before i start throwing Ben Franklins at parts ? Perhaps a diagnostic flow chart ?
Any and all help is greatly appreciated.
No DTC’s except a 4x4 hi voltage and a trans signal code.

I have narrowed it down to 4 wires coming from a grey 25 pin connector under the fuse box. It is located under the bottom 4 relays. Wire colors are white with blue,white with brown, white with lt green, and white with dark green. Each is pulling around.5 amps as it fluctuates.