Parking lights issue

2002 Tundra SR5…parking lights stay on when turned off but dimmer than when turned on. Have to disconnect the battery to turn lights off, any ideas and/ or a schematic?

 

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Have you changed bulbs to LED or made any other mods to the lights?

 

One of many tips in this thread, I'm bolding the part that is quite likely your issue, especially if your windshield was ever replaced, or it's cracked, but even if neither of those are true:

• These trucks usually don't have a ton of other electrical issues. Hidden corrosion inside the battery/alt cables happens. Sometimes, a couple thousand miles after timing belt changes, people will have startup issues because the crank position sensor wasn't properly tucked away and gets rubbed by a belt (pic). There's also a similar problem with camshaft position sensor under the cam cover, where the belt will rub through (pics). There's the rodent issues mentioned earlier. Occasionally, water leaks can send water down into the ECM behind the glovebox (pics), or into the fusebox inside the cab/dash (pics & pics & pics, it happens a LOT). Many drain/vampire issues trace back to aftermarket add-ons whether the owner knows they exist or not - alarms as mentioned earlier, brake controllers, poorly installed trailer receptacles, those are some big ones.

You should really check for evidence of water leaks into the fusebox. It happens so frequently, we probably have about a dozen threads we can reference. But moreover, if it is, you need to figure out HOW the water is getting in. Usually comes from the outer windshield seal or the a-pillar.

 

No upgrades or bulb changes, but the park lights were left on a few days prior. Im thinking maybe the relay under the dash by the steer column which clicks when the park lights are turned on may have some tips that are comprimised.

 

If that's true, it's probably compromised for a reason, water intrusion. It's totally possible a relay is bad but I doubt it.

The water will usually get in from higher up, then trickle down the wire bundles, right into the back of the "integration relay" (aka fusebox).

Sometimes you can just pop off a couple of connectors or relays and check for traces. It may be subtle, but will look like THIS, little traces of green copper oxide.

 

Very possible water contamination, I’m in south Florida and have been driving in extreme rain conditions this past week. Will inspect noted areas… thank you all for input, will post findings.