Hint:
Past problems that seem unrelated may also help in some cases.

Operation flow
Symptom confirmation and diagnostic trouble codeTaillight relay circuit
Description
When the light control switch, located on the headlight dimmer switch, is
turned to the tail position, the
taillight relay (marking: t-lp) turns on to illuminate the front side marker
lights, rear taillights, side marker
lights and license plate light.
Wiring diagram
Ins ...
Front seat assembly (for power seat type lh side)
Components
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Rear seat outer belt assembly
Components
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