1977 Toyota Sienna - Light still on

have had 3 diagnostic test costing hundreds od dollars. Light still come on. even tho they all claimed they fixed it

That’s unfortunate. If you have someone read the code(s) turning on the light (in the form pxxxx) and post them, we may be able to provide some direction for you.

What kind of light? I don’t think any 1977 vehicle had OBD.

Which light ?
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