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Sometimes when I push a shift button there is a steady clicking from the shift relay, and I have to push another button and try again. I've changed the shift relay, cleaned the contacts in the push button unit, made sure the wire connector at the fire wall is clean & all connected. All of that seems fine, but the problem persists. Haven't yet taken the unit on the trans off & apart because it is a pain to remove. Any suggestions? Do you think the problem is in the fingers in the shift unit on trans? Thanks,
Clifford

Very possibly the fingers but unless a finger was caught by the sector and bent they usually fail or wear to the point contact to the segment is lost and nothing moves or else it may stop and start a time or two when a particular button is pushed. A terminal loose or coming out of the plastic plug under the dash can have the same symptom.

It could also be the anti hunt adjustment on the actuator has worn or is out of adjustment. It sort of depends on what gear the transmission is in and what button is pushed when it happens. It almost sounds as if the clicking is because the actuator is going past where it needs to stop and then rapidly reversing a time or two going back and forth as it overshoots when trying to stop at the proper point. Each time the motor reverses there is a distinct click from the shift relay. Usually though it only clicks a few times before it finally is able to stop.

A less likely cause could be the auto park relay sticking or not actuating when ign sw is turned on so is still powering the park finger when another button is pushed and powers its finger. In that scenario the actuator wants to go both directions so does not know what to do. Usually if that has happened there is more of a loud buzzing than clicking sound coming from the shift relay. If left in that condition long enough the circuit breaker opens or damage to the motor occurs.

You can test for hunting and finger connections by watching the shift relay status. Connect a test light or meter to each of the direction connections, Orange & Black wire and Pink wire (terminals 4 and 6). If the actuator is hunting, the lights will alternate. If the finger connection is intermittent, one light will blink.

You would expect the probability of a first order hunting overshot to increase with the distance between the current and target gears. The physical gear order is PNHDLR.

Of course testing would be easier with a Push Button Test Box.

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