Detector rails do not power adjacent powered rails upward on slope

Powered rail don't update when minecart drive below presure rail.Only happen if going uphill.Try use pressure rail -> powered rail -> pressure rail -> powered rail.Hard to explain.Tomorrow I give video to provide this issue.

Update:Thanks Mega_Spud for screenshot.
Only happen if cart moving to uphill.If the cart places in uphill at detector rail next to powered rail,the powered rail behavior as normal