MSP430F5132 - MPPT & LED Driver - PMP7647

Hi, we have replicated the PMP7647 board and are now testing it. However, we faced the following issue:= We are facing the the some issues as follows.: 1. Connected the battery at battery terminal , load at L+ & L- . We turned ON the I/P DC Source (I.P vtg set to 18V) & We have measured the 12VDC at O/P (L+ , L-) terminal. But if DC source turned OFF then also we have received 12 V at O/P (L+ . L-) which should actually want to cut OFF. 2. Connected the battery at battery terminal , load at L+ & L- . When we turned ON the I/P supply (from DC Source), observe that the battery was not charging. But If we turned ON the I/P supply first & then connect the battery in the ckt, Observe that the Battery was charging. Why this sequence need to be followed ? Kindly advise Atul Bhakay