Sounds like you have a loose connection somewhere. An 03 on the fault code display means power was interrupted. Make sure the ECU connector is in solidly and latched, check the ECU relay as well while you're down there under the seat and check your battery cables at both ends, all connections.
'91 RRC-4.2, R380, LT230, GDE bumper with Smittybuilt 8K winch, Custom 3" lift, 33's, Equipe trailing arms, Rock Ware sliders, Custom diff guards, Maxyedor HD steering, TT/Detroit, Rovertracks axles
'61 Series II 88"
'94 RRC County LWB
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