C15 – Idle Shutdown Timer – Test

System Operation Description: “Idle Shutdown Timer”

The “Idle Shutdown Timer” is intended to improve fuel economy by limiting idling time.
The “Idle Shutdown Timer” is a “Customer Specified Parameter” that may be programmed for any period from 3 to 1440 minutes.

The timer is activated when all of the following conditions are met regardless of the position of the parking brake:
• The vehicle speed is 0.
• The engine is not in “Cold Mode” or “Dedicated PTO Mode”.
• The engine is not under load.

The timer can be reset by moving the vehicle or the timer can be reset by quickly depressing the accelerator pedal and releasing the accelerator pedal.

The check engine lamp will begin to rapidly flash 90 seconds before the programmed time expires.

During this 90 second time period, the following conditions can disable the timer:
• The driver moves the clutch pedal.
• The driver moves the service brake pedal.

The following event code will be logged when the driver overrides the timer by the use of the clutch pedal or the brake pedal during the 90 second period:
• 71-00 Idle Shutdown Override

If the parameter for the “Allow Idle Shutdown Override” is programmed to “NO”, the timer can not be overridden by the use of the clutch pedal or the brake pedal during the final 90 second period.

“YES” is the factory default that is programmed for the parameter for the “Allow Idle Shutdown Override”. The allowance of the override is the default.

An additional parameter can be programmed to allow the timer to be reset above a specified engine speed. When the “Idle Shutdown Timer Maximum RPM” parameter is programmed to a value below the Top Engine Limit, the timer can be reset by increasing engine rpm above the programmed limit. The timer will be reset until engine rpm drops below the programmed value. The timer will begin counting again. The factory default of 2120 rpm disables this feature. The “Top Engine Limit” is 2120 rpm.

If the timer is activated and the timer is allowed to shut down the engine the following event code will be generated:
• 71-01 Idle Shutdown

Code 71-01 records the event and the code does not indicate an electrical system malfunction or an electronic system malfunction. Disable the timer by programming “Idle Shutdown Timer” to 0 (Caterpillar Factory Default).

The ECM will shut down the engine but not the vehicle electrical system when the “Idle Shutdown Timer” time expires. The “Engine Shutdown Output” can be used to shut down the vehicle electrical system after the “Idle Shutdown Timer” time has expired.

The “Idle Shutdown Timer” feature can be temporarily disabled by the use of the electronic service tool. The “Idle Shutdown Timer” feature can be temporarily disabled through the “System Troubleshooting Settings” screen in order to help troubleshoot other problems. Temporarily disabling this feature avoids engine shutdowns when you are troubleshooting other systems. The use of this method eliminates the need to temporarily alter the customer specified parameter of “Idle Shutdown Timer”.

Note: If the following diagnostic code is active, the “Idle Shutdown Timer” will not operate.
• 84-08 Vehicle Speed signal out of range

Note: The timer will be overridden if the following conditions exist.
• The “Allow Idle Shutdown Timer Override” is programmed to “Outside Temperature Based” or “J1587 Outside Temperature Based”.
• The temperature that is being sensed by the ECM is below the minimum air temperature that is programmed or the air temperature is above the maximum air temperature that is programmed.

Test Step 1. Verify Activation of the “Idle Shutdown Timer”
A. Connect the electronic service tool to the data link connector.

B. Access the “Configuration” screen on the electronic service tool.
a. Access the following display screens in order:
• “Service”
• “Configuration”

b. Record the programmed time for the “Idle Shutdown Timer”. The “Idle Shutdown Timer” must be between 3 and 1440 minutes. If the “Idle Shutdown Timer” is programmed to 0, then the timer is disabled.
c. Record the programmed status of the parameter for the “Allow Idle Shutdown Override” and the “Idle Shutdown Timer Maximum RPM”.

C. Start the engine. Allow the engine to warm up until the coolant temperature is 38 C (100 F).
Allow the engine to operate at the programmed low idle and turn off any unnecessary accessory devices.

D. Ensure that all unnecessary loads are turned off. The “Idle Shutdown Timer Maximum RPM” can be programmed to allow the timer to be reset by increasing the engine RPM above the programmed limit. Ensure that the accelerator is not being depressed so that the rpm increases beyond the programmed limit.
a. Park the vehicle.
b. Ensure that the status for “Vehicle Speed” on the electronic service tool is 0 km/h (0 mph).
c. Ensure that the engine speed on the status screen is at “Low Idle”.
d. Ensure that the clutch pedal is not depressed.
Ensure that the brake pedal is not depressed.
e. Ensure that the status of the PTO On/Off Switch is off.
f. Observe the “Idle Shutdown Status”.

Expected Result:
Result 1 The “Idle Shutdown Status” indicates “Counting”.
Result 2 The “Idle Shutdown Status” indicates “Not Active”.

Results:
• Result 1 – The ECM is reading the proper conditions for the activation of the “Idle Shutdown Timer”. Proceed to Test Step 2.
• Result 2 – The ECM is not reading the proper conditions for activation of the “Idle Shutdown Timer”. Proceed to Test Step 3.

Test Step 2. Verify the Driver Alert Function for Idle Shutdown and the Override Function for Idle Shutdown

A. Connect the electronic service tool to the data link connector.

B. Access the “Configuration” screen on the electronic service tool.
a. Access the following display screens in order:
• “Service”
• “Configuration”
b. Record the programmed time for the “Idle Shutdown Timer”. The “Idle Shutdown Timer” must be between 3 and 1440 minutes. If the “Idle Shutdown Timer” is programmed to 0, the timer is disabled.
c. Reprogram the “Idle Shutdown Timer” to 3 minutes for this test.

C. Observe the following items during the 90 second period before the programmed shutdown time:
• Check Engine Lamp
• Idle Shutdown Status

D. If the customer parameter of “Allow Idle Shutdown Override” is programmed to “YES”, perform either of the following actions in order to override the shutdown:
• Press the clutch pedal.
• Press the service brake pedal.

Note: This action must be accomplished while the check engine lamp is flashing. The check engine lamp flashes during the 90 second period before the programmed shutdown time.

E. Reprogram the “Idle Shutdown Timer” to the value that was recorded earlier for this test.

Expected Result:
During the 90 second period before the scheduled shutdown, the status should change from “Counting” to “Driver Alert” and the check engine lamp should flash rapidly. If the “Allow Idle Shutdown Override” is programmed to “YES”, the “Idle Shutdown Status” should change to “Override” after the pedals are depressed.

Result 1 The “Idle Shutdown Timer” behaves in the manner that is described above.

Result 2 The check engine lamp did not flash during the alert.
Result 3 The ECM did not sense a change in the status of the service brake.
Result 4 The ECM did not sense a change in the status of the clutch.

Results:
• Result 1 – The “Idle Shutdown Timer” is operating properly. STOP.
• Result 2 – The check engine lamp did not flash during the alert.

Repair: Perform the following diagnostic procedure: Troubleshooting, “Check Engine Lamp Circuit – Test”

STOP.

• Result 3 – The ECM did not sense a change in the status of the service brake.

Repair: Perform the following diagnostic procedure: Troubleshooting, “Service Brake Pedal Position (Switch 1) Circuit – Test”

STOP.

• Result 4 – The ECM did not sense a change in the status of the clutch.

Repair: Perform the following diagnostic procedure: Troubleshooting, “Clutch Pedal
Position Switch Circuit – Test”

STOP.

Test Step 3. Check the State of the Related Conditions when the Vehicle is Parked

A. Check the state of the following related conditions when the vehicle is parked:
• Ensure that the vehicle speed is 0 km/h (0 mph) on the electronic service tool or the dash display.
• Ensure that the engine is not in cold mode.
(The status screen on the electronic service tool will indicate that the “Cold Mode” is “Active” in the corner of the display screen.)
• Ensure that the PTO On/Off switch is OFF.
• Ensure that the engine is at low idle.

Expected Result:
Result 1 Vehicle speed is not indicated as 0 km/h (0 mph).
Result 2 The status screen on the electronic service tool indicates that the engine is in cold mode.
Result 3 The status of the PTO On/Off switch is not “OFF”.
Result 4 The engine is not at low idle.

Results:
• Result 1 – Vehicle speed is not indicated as 0 km/h (0 mph).

Repair: Perform the following diagnostic

procedure: Troubleshooting, “Vehicle Speed Circuit – Test”

STOP.

• Result 2 – The status screen on the electronic service tool indicates that the engine is in cold mode.

Repair: The engine must not be in “Cold Mode” operation while this test procedure is being performed. Allow the engine to run until the coolant temperature exceeds 20 C (68 F).
Troubleshoot and repair any related conditions.

STOP.

• Result 3 – The status of the PTO On/Off Switch is not “OFF”.

Repair: Perform the following diagnostic

procedure: Troubleshooting, “PTO Switch Circuit – Test”

STOP.

• Result 4 – The engine is not at low idle.

Repair: Return the engine to low idle. Perform the test procedure again.

STOP.

 

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