938K High Idle?

[DevinJ]

We have a 938K and I am trying to do the auto brake system test. I can't figure out how to turn on high idle and that is the one of the conditions to do the tests. Appreciate any help.

 

[Nige]

Are you testring service brakes or parking brake.?
What test procedure are you using.?
For High Idle on a machine of that size is it not simply a case of pressing the accelerator pedal all the way to the floor.?

 

[DB2]

On ours if you engage forward or reverse the idle increases to 1000. I guess due to the hydrostatic drive.

There is a throttle control accessed through display.

 

[DevinJ]

Are you testring service brakes or parking brake.?
What test procedure are you using.?
For High Idle on a machine of that size is it not simply a case of pressing the accelerator pedal all the way to the floor.?

The service brakes and parking brake. When you press the brake pedal it goes into neutral and you can't turn that off from what I see so the self test seems like the only way.
There is a button on the machine that you hold for 2 seconds and it does a self test.

 

[DevinJ]

On ours if you engage forward or reverse the idle increases to 1000. I guess due to the hydrostatic drive.

There is a throttle control accessed through display.

I will try that but the screen says to put the machine in neutral then hold the test button for 2 seconds and it does a self test.

 

[kshansen]

As always any chance of a S/N so someone could feel confident they are looking at the information for your machine?
A quick look at 938K in SIS shows five or six serial number prefixes so I don't want to guess wrong and give incorrect information. They may all be the same but I'm not going to search each and every one and compare them.

 

[Nige]

You mean the test on the attachment, specifically the highlighted point on Page 2 regarding High Idle..?
Press the accelerator pedal to the floor during the test. The engine RPM signal will be an input into the Transmission & the Brake ECM's.

 

[Per Eriksson]

Are you following this?

The purpose of the Service Test button on the keypad is to provide the operator a method to manually test the Service Brake, the Parking Brake, and Secondary Steering (if equipped). The left light is the Service Brake. The middle light is the Parking Brake. The right light is Secondary Steering.

Press the Service Test button to cycle between the three Service Tests. If Secondary Steering is not installed, the test will only cycle between the first two Service Tests. Press and hold the button to activate the Service Tests assuming all other criteria are met. While the Service Test is active, the light for that test will blink.

The following criteria must be met to activate each Service Test:

Service Brake

• The light for the Service Brake Test must be on.
  
  
  
• The machine must not be moving.
  
  
  
• Depress the left pedal at least 95 percent.
  
  
  
• The parking brake must be disengaged.
  
  
  
• Engine speed must be greater than 1700 rpm.

1. Press and hold the button for 2 seconds.
   
   
   
2. Shift the transmission selector to Forward or Reverse.
   
   
   
3. The machine must not move.
   
   
   
4. If the machine moves, repair or adjust the service brake before putting the machine into service.
   
   
   
5. Return to Neutral to complete the test.

Parking Brake:

• The light for the Parking Brake Test must be on.
  
  
  
• The machine must not be moving.
  
  
  
• The service brake depressed less than 10 percent
  
  
  
• The parking brake must be engaged.
  
  
  
• Engine speed must be greater than 1700 rpm.

1. Press and hold the button for 2 seconds.
   
   
   
2. Shift the transmission selector to Forward or Reverse.
   
   
   
3. The machine must not move.
   
   
   
4. If the machine moves, repair or adjust the parking brake before putting the machine into service.

Secondary Steering: (If Equipped)

• The secondary steering option must be installed.
  
  
  
• The key must be on and the engine must be off.
  
  
  
• The parking brake must be engaged.

1. Press and hold the button for 2 seconds.
   
   
   
2. The secondary steering indicator will display on the LCD of the instrument cluster for 10 seconds.
   
   
   
3. While the test is running, provide the following steering inputs:
   
   
   • Steer left
     
     
     
   • Steer center
     
     
     
   • Steer right
     
     
     
   • Verify that the movement of the machine aligns with the steering input
   
   
   
4. If the secondary steering does not turn on, repair the system before putting the machine into service.
   
   
   
5. Return to Neutral to complete the test.

 

[DevinJ]

Here is what I am working with. You guys have been amazing btw. Thanks for all the help so far!

 

[Nige]

To get High Idle RPM it appears as though operator input is required in the form of physically pressing the accelerator pedal and then press the test button.

 

[DevinJ]

To get High Idle RPM it appears as though operator input is required in the form of physically pressing the accelerator pedal and then press the test button.

I tried that at 1200rpm, 1800rpm, and full throttle. I am lost on this one, I sure wish we had the manual for it