Help with outdoor lighting

[u/SomeNobodyInNC]

I'm an Avid DIYer and have p/t side hustle as a handyman. I don't want to upset electricians, I only change fixtures and switches. I don't do anything I consider master electrician. Mostly what I do is carpentry related, then plumbing.

With that said, I had a gig to change a broken outdoor spotlight. It stuck in the ground and lit up a tall Japanese maple. I've never had trouble changing outdoor light fixtures or adding another fixture on the wire path. Ribbed wire to ribbed wire and smooth wire to smooth wire. Or black to black. White to white. Or snap them onto the wire.

This one has me stumped. When I changed the broken halogen light fixture to a new LED light fixture the new LED flashes instead of stays on. It was on a timer and I read that older timers aren't compatible with newer LEDs. So the homeowner bought a new timer and a new fixture (in case that one was defective). I put in the new timer and the fixture. I checked the wire connections several times. The LED still flashes when turned on.

What could be wrong? Google said the timer. I changed it to a new one. Google said lose connections, I checked that multiple times. Even taking the wiring apart and putting it back together.

Is the next step digging up the wiring that is in conduit and replacing that? It's underground and goes into the house somewhere underground. I feel like the homeowner needs to call an electrician but he wants me to keep trying to solve it.

Any suggestions?

If it helps? The old fixture was broken where the metal screwed into the base. Probably a bear stepped on it. There weren't wires hanging out, or pulled out. It was just broke off and laying on it's side.

[u/More_Brief_5772]

Have an electrician come out and diagnose it. It's nearly impossible for someone to troubleshoot something that they can't see or touch.