Cruise Control(PTO) system doesn't turn on.

[makintosh8]

Hi for all,
In our service we doing small maintenance for Peterbilt Truck with next specs below:
Model.378
chassis WT 16729
VIN: 1KP-FDT9X-X-2D577371
MFG.Peterbbilt Motor Company
a division of PACCAR
Denton , TEXAS U.S.A.
With CAT C-10 Engine
Ser No.3CS24913
ECM Software 208-5743

Description of a problem:
On the Truck the Cruise Control system doesn't turn on.
Namely , when we turn the PTO switch in position ON , then on Dashboard panel the PTO lamp start working. But, when we put the near switch to position SET , the RPM is not increased.
I checked all wires from the switches till ECM ,switches and connectors and don't found any damages or failure.
My question it is possible to deactivate the PTO mode in ECM through CAT-ET software or not?
Also,will glad for everybody,who already had the same problems,found out the resolution for it and will kindly to advise the decision of this malfunction.

Regards,

Me.

 

[wcdiesel]

Yes you can deactivate it with et , you,ll need to check your parking brake switch and trans neutral switch if fitted , both will stop your set switch working

 

[2xR]

Yes you can deactivate it with et , you,ll need to check your parking brake switch and trans neutral switch if fitted , both will stop your set switch working

That would be my first guess. Many times I have backed under a trailer that, of course, had locked brakes, therefore I didn't set the tractor brake. I sat there ten minutes wondering why the engine wouldn't idle up before it dawned on me. I'm a slow learner, cuz I still do this from time, to time.... It just don't take me ten minutes the remember what the problem is, anymore.