... check voltage to the starter?

You've got your main 12V feed off the battery, and two additional much smaller wires to the solenoid.

One of these smaller wires is the 12V signal from the key. Put 12V to this wire, and it will pull in the solenoid and turn the starter.

When troubleshooting, always look at what was changed before checking other nondisturbed areas.

Jim

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14 E250 BlueTEC black. 45k miles
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