Gateway 504 error when switching from http to https

[kkyen]

guys... i have an application which is previously configured under http. The application just got upgrade at backend with https, SSL. So i need to enable https as well in AM. Basically it was running fine after switching to https, however there is a link/page having problem by returning gateway 504 error, but this error doesn't happen when it was under http.

How should i trace this? Or what is the correct log i should trace under Access gateway?

(AM 3.0.3)