Hi Mrs Ting, I dont't have any teenagers yet but i've worked with many of them before. So i can only share with you some of the reasons causing teenagers to drift away from parents. Instead of solving the problem straightaway, it will be good to identify what cause the problems.
Common problems.(not statistically proven but these were based from my interaction with teenagers) Usually, they mention something along these lines. But i've kindda edit and rephrase them.
1) My parents and I dont't share the same interests.
2) Before i can explain A-Z, my parents 'shoot' my words/ideas down.
3) They dont't have time for me so why bother to even talk to them.
4) I worry about the expectations they may have set for me and i dont't want to upset them or make them think i am a failure. So to avoid myself in the dilemma, i simply 'avoid' them.
Once you have identified what causes him to have minimal communication with you, you may want to start by analysing your role first (compare what you have done last time and what improvement you can make now), finding out his likes and dislikes and after that organise some activities that you know both of you can enjoy together. Normally, through shared fun activities, a person may start to ask questions or open up his/her thoughts unconsciously. That is a good start to generate a two-way communication.
Hope it helps.