Alanarkison
Member
Has anyone ever taken and recorded the voltage readings at the throttle/Morse lever on a Volvo TAMD74P EDC? its a twin engine installation where one lever for each engine does the gear shift and throttle?
Ive got the following readings taken when the engine is stopped but the ignition is on.
I can't find anything in the manual with a definitive voltage range. Both potentiometers showing exactly the same resistance readings. Worth noting that the potentiometer used is the same type for both port and starboard levers. It just gets flipped to either side therefore on one side the voltage will go up and the resistance goes down and vice versa on the other lever.
On the 3 pins from the EDC to the throttle levers, Pin 1 is 5 volts, Pin 2 is 0 Volts and Pin 3 is the signal to the ECU for throttle position. When measuring between Pin 1 and Pin 2 I should get 5 volts but I get 4 volts. If I unplug the the potentiometer I then have 5 volts between pins 1 and 2 so the potentiometer is causing the loss of 1 volt at neutral. Would have thought that with only 4 volts in then its inevitable that the output signal to the EDC will be lower. Not sure if that has anything to do with it but have added it for info.
Appreciate any thoughts.
Thanks
Alan
Ive got the following readings taken when the engine is stopped but the ignition is on.
I can't find anything in the manual with a definitive voltage range. Both potentiometers showing exactly the same resistance readings. Worth noting that the potentiometer used is the same type for both port and starboard levers. It just gets flipped to either side therefore on one side the voltage will go up and the resistance goes down and vice versa on the other lever.
On the 3 pins from the EDC to the throttle levers, Pin 1 is 5 volts, Pin 2 is 0 Volts and Pin 3 is the signal to the ECU for throttle position. When measuring between Pin 1 and Pin 2 I should get 5 volts but I get 4 volts. If I unplug the the potentiometer I then have 5 volts between pins 1 and 2 so the potentiometer is causing the loss of 1 volt at neutral. Would have thought that with only 4 volts in then its inevitable that the output signal to the EDC will be lower. Not sure if that has anything to do with it but have added it for info.
Appreciate any thoughts.
Thanks
Alan
Last edited:
