Combines digital reading on a 1460

[hot_rod]

You might check the air gap on the rpm sensor on the pto housing or check the conector for the sensor.

 

[hot_rod]

You might check the air gap on the rpm sensor on the pto housing or check the conector for the sensor.

 

[dale3]

If you have a buddy with a 1400 series you can switch the heads real quick to eliminate the head. It sounds to me there is a problem in the processor in the head.