I am new to the forum. There is a lot of great info here.
A friend of mine bought a new house and it has an old Catalina spa. The spa shell says 1982 Polynesian Pools and Spas Inc. The control board is a BL-40 universal for the Catalina and Brett Aqualine. My problem is that when I push the button to turn on the underwater light the GFCI immediately trips before and now after I drained the spa. I have taken the light apart and there was a small amount of water. I dried it out but it still trips. I have disconnected the remote panel and jumped the light relay and the circuit trips. I have bypassed the control board all together and connected just the light to the GFCI breaker and it still trips. I am thinking that the light assembly is bad. The problem is that the spa is buried in the ground with a small deck around it and I am not sure how to access the wiring to pull the light assembly. The assembly has a bolt that the wiring goes through but when I loosen the bolt I can't remove the wires.
How can I access the wires.
Thanks in advance.

Sounds like the light assembly is bad (I bet it is a submerged pool type light), unless you want to dig a trench, do without the light. If it was leaking, definitely replace or remove the wiring to it. In ground makes it tough!

Thanks for the hep Jeff. You are correct it is an under water pool type. So I am correct in assuming that the wiring can not be removed at the light assembly?

The wire usually swells up and won't come out. The wire is part of the light assembly.