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The starter relay gets it's ground from the gear selector relay.
Look around gear selector there will be at least two micro switches,,in order for it to start both need to agree,,in order to shift forward one will close and one will open,,the opposite is true for reverse.So the starter relay gets its ground from gear shift relay.
Most times the little springs inside micro switches get weak and don't go back open or closed.
Make sure to look at how they are wired,, N/O,, or NC,, before replacing,,, as they can be wired either way.
I replace both at the same time.
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