310SL hand throttle problem.

[Canadian_digger]

Have a 2017 310SL It’s a tier 3. Has around 1500hrs on it. The other day my operator called me to inform me the hand throttle quit working and would not rev up the motor. But the foot throttle was working properly. The throttle ended up working intermittently for the rest of the day. He managed to finish the day and floated it back to the shop. When he got back I unloaded it to put it in the shop for the night. It was late and decided to look at in the morning.

In the morning I started it up and a code came on right away. High voltage. It was producing around 17-18 volts. So I had the alternator rebuilt. Throttle was still the same. So I replaced the hand dial switch thinking the high voltage damage it. It did not fixed the problem. Hand throttle still worked intermittent.

Any ideas where to look? Could the voltage have damaged the ECM?

I have a 2018 310SL. Basically identical machines. Could I swap ECM to see if that is the problem.

 

[AzIron]

Check the switch on the seat rotation they are wired into the circuit to chop the throttle if you spin back forward without moving the hand dial

I have had the switch not activate right before a handful of times and it will not allow you to throttle up from the hand or sometimes the foot. Usually if you release the seat and swivel enough to relatch the seat it sets the switch and your in business


If that's not it I would think it's a loose ground before the ecm but I am not an expert but if it's in the ecm 99 percent of the time it will have a code

If it does have code your dealer can read it through jd link

 

[Canadian_digger]

Aziron thanks for your reply. I have had switches in the seat fail in the past. When they started acting up it would also kick off the rear hydraulic. Or the buzzer on the dash would warn of rear hydraulic active even though the seat was in the rear facing position.

None of that is happening this time.

I could check the switches in the seat to double check.

No active codes at the moment. Only when I had the high voltage.

 

[mg2361]

Check if your brake lights are on or stay on intermittently after brake application. If the brake light pressure switch fails or acts up intermittently it will kick the throttle to idle (with no codes).

 

[Canadian_digger]

Check if your brake lights are on or stay on intermittently after brake application. If the brake light pressure switch fails or acts up intermittently it will kick the throttle to idle (with no codes).

Bingo! You hit the nail on the head. The brake lights stick on once and a while.

Love this site and it’s members. Once again saved me time and money. Hope I can return the favour.

 

[AzIron]

That's awesome I will have to remember that one