To operate or test the starter from under the hood, the Service Socket connects to Starter terminal 50. (Via the Neutral Safety Switch if car has Auto Transmission.) A jumper wire from Battery + to the Service socket should energize the starter solenoid (assuming the Neutral Safety Switch is good).

The Service Socket, and a test light or meter, can also be used to see if the Ignition Switch is sending +12v to the Starter when in position III (at least as far as the NSS).

Here is a 240 Service socket:


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Look for a short wire coming out of the thick bundle that crosses the upper firewall— about 6" long with female spade terminal inside Black plastic housing. Wire color is Pink on '92, but probably covered by black insulation.

The 940 Service Socket (Blue) is shown below:



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