[Stephen Edwin]

David,

Have you tested Tom's brake lights without the ignition switched on? His actual vehicle? This is a check absolute basics time.

The diodes are a tad of a mystery and mysteries are not good when trying to solve problems.

Tom,

Additional question. You have searched around the vehicle. Have you found anything that might be a relay as surmised by David? Wired to the load area light switch?

Overall,

If "we" work through the basics, like my list of questions. We might find some definite information.

There really might come a time to get an auto electrician to look in to this, checking out the actual wiring on the actual vehicle.


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