Have 87 k5 Blazer with rear window not operating properly. Have tried taking cover off and appears to operate fine going down but will not go up with door closed unless I push several times on left side of door while pressing up on button. Played with latches while door open and could get good up operation with left switch in certain position but unable to obtain this position with door shut. Is there a was to disable the latch function that keeps window from operating? I'm missing something, please help. Any ideas would be greatly appreciated. Thanks.

Check for a switch there.