Installed remote in fan. Having problems with fan and light. Off/on , speed, and light dimming. Do I need to bypass pull chain wiring if so which leads should I splice. Tried with pull chain for fan on high, and light on, but this doesn't work

If you have pull chains and a remote the pull cahins should be set to high speed and brightest light, then leave them alone after that and just use the remote. Do not bypass or spice anything

I agree with Ballenger. If you are having problems it is with the remote.

Ceiling fan remote controls - help and FAQ- Ceiling Fans N More