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Neutral/park saftey switch/94 Buick

Is there any way to test this switch. Turn key on and go to ignition and no starter response. Battery good, and when I jumper the starter, it turns freely. Vehicle is a 94 Buick Park Ave Ultra SC 3.8. Is there a way to test the switch without removal? I have tried following wiring from the steering column down but it is overwhelming. I also followed steps to insure that the antitheft key protection was in proper function.

Any suggestions? Thank You

You can test for start voltage at the end of the wire at the starter solenoid. Disconnect the small wire from the starter solenoid. Attach your positive test probe of your electrical multimeter to the disconnected wire terminal. Touch the negative probe to ground. Have someone to turn, and hold, the ignition key at START, while you take a dc voltage reading. A voltage reading lower than the battery voltage indicates a resistance, in a switch or a connector, between the starter solenoid and the ignition switch. Then, keep following the wire, and taking voltage readings back toward the ignition switch.

Have you tried shifting the transmission into neutral and then try starting the engine? If the engine starts when doing this there’s a problem with the park/neutral safety switch.


From START, in the ignition switch, a yellow wire goes to the “starter enable relay”. This may, also, be called the “start run” relay which is here:,4294931079/shopping/locsSelect.htm
From this relay, the yellow wire go to the “park/neutral” switch (neutral safety switch) which is actuated by the gear shift linkage. Then, the yellow wire goes to the starter solenoid.
If the Passkey II Decoder Module is preventing starter operation, by-passing the enable relay may allow you to crank the engine. To by-pass the enable relay, take the yellow wires going into, and out of, the enable relay, and connect them together.