If it was mine, I would "diagnostically" do a temporary bypass of the OD relay — replacing it with a jumper wire at the relay harness connector plug by connecting these two terminals together:
• Input terminal #15 (2 wires, a Blue-Black and a Gray)
• Output terminal #87 (White wire)

A good-fitting jumper can be made with flat male crimp-on terminals that are the same size and shape as the relay terminals. This jumper wire will simulate a relay that is always energized — which is the normal condition, until the shifter button is pressed.

If the fuse still blows, the most likely suspect is the output White wire to the solenoid. Or, less likely, the Gray wire from the shifter switch to the relay.

If the OD now works OK and the fuse doesn't blow (and you don't need the shifter button downshift option), you can just leave the jumper in place.


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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.