Quick Answer
Okay so here's the quick version. Nine times out of ten your pool light is out because the bulb is toast or the gasket failed and let water in. You can probably change the bulb and gasket yourself for under $50 if you're careful. First, KILL the power at the breaker. No exceptions. Pull the fixture onto the deck—there's plenty of cord. If you see water inside or the breaker keeps tripping, you've got a bigger problem. That's when you call a guy like me, and you're looking at a few hundred bucks, easy.

Common Symptoms
Possible Causes
Step-by-Step Diagnosis
Step 1
KILL THE POWER. Go to your main breaker panel and flip the breaker for the pool light to the OFF position. Tape it off as a safety precaution.
Step 2
Visually inspect the fixture from the pool deck. Look for obvious cracks in the lens or signs of water inside.
Step 3
Remove the single screw at the top of the light fixture. Pivot the fixture out of its niche and gently pull the excess cord to bring the entire housing onto the pool deck.
Step 4
Open the fixture housing by removing the clamp or screws. Inspect the interior for water, corrosion, or a visibly burned-out bulb (blackened glass, broken filament).
Step 5
Examine the rubber gasket for cracks, brittleness, or deformities. If any water was present, this gasket has failed and must be replaced.
Step 6
If the bulb appears to be the issue, replace it with a new one of the correct voltage and wattage. Always replace the gasket at the same time.
Step 7
Reassemble the fixture, ensuring the new gasket is seated perfectly and the housing is tightened securely and evenly to create a waterproof seal.
Step 8
Before submerging, perform a brief test by turning the power on for a few seconds to confirm the new bulb works, then immediately turn the power back off.

DIY vs Professional Costs
| Repair Type | DIY Cost | Professional Cost | Time Required |
|---|---|---|---|
Bulb & Gasket Replacement | $30-$200 | $200-$350 | 1-2 hours |
Full Fixture Replacement (LED) | $300-$600 | $500-$900 | 2-4 hours |
GFCI Breaker Replacement | $40-$80 | $150-$300 | 1 hour |
When to Call a Professional Pool
- If the circuit breaker or GFCI continues to trip even after you've tried basic fixes. This indicates a persistent and dangerous short circuit.
- If you open the fixture and find significant water damage, corrosion, or rust. The entire fixture likely needs replacement, which is a more involved job.
- If the wiring in the fixture or the cord leading to it appears damaged, frayed, or cracked.
- If there is not enough cord to pull the light fixture completely out of the water and onto the pool deck.
- If you are at all uncomfortable or inexperienced with electrical work, especially in a wet environment. It's not worth the risk.
Prevention Tips
- Always replace the rubber gasket every time you replace the bulb. It's cheap insurance against water leaks.
- Upgrade from an old incandescent light to a modern LED fixture. They last significantly longer, use less energy, and run cooler, which is better for the seals.
- Periodically inspect the light fixture for any visible signs of moisture behind the lens, cracks, or wear.
- Ensure the light is turned off when not in use to extend the bulb's lifespan and reduce heat stress on the components.

Frequently Asked Questions
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