Steps for finding Branch Current by Thevenin’s Theorem:
i) Identify the load branch whose current is to be found.
ii) Redraw the circuit with load branch separated from the rest of the circuit such that the the load branch appears between terminals, say A and B, which are connected to rest of the circuit by two wires.
iii) Remove the load branch from terminals A and B, so that the rest of the circuit appears between these terminals A and B.
iv) Find the open circuit voltage appearing across the terminals A and B (after load removal) due to internal independent sources, using any circuit analysis technique. Let this open circuit voltage be VTh.
v) Determine the equivalent impedance of the circuit seen between the open terminals A and B, while looking back into the circuit, with all internal independent voltage sources replaced by short-circuit and all internal independent current sources replaced by open-circuit. Let this equivalent impedance be ZTh.
vi) The circuit appearing between open circuited terminals A and B (due to removal of load branch) is now represented by simple circuit consisting of a voltage source, having magnitude VTh in series with an impedance ZTh.
vii) If the load impedance is ZL, then connecting it between terminals A and B gives rise to load current IL = VTh / (ZTh + ZL)