LAMP 1631883 - Caterpillar

Recommended Actions
Note: If the problem only occurs under certain conditions, test the engine under those conditions. Examples of certain conditions are high engine idle, full load, or a specific operating temperature. Troubleshooting the symptoms under other conditions may give misleading results.
Table 1
Troubleshooting Test Steps Values Results
1. Check for Active Codes and Logged Codes
A. Establish communication between Cat Electronic Technician (ET) and the Electronic Control Module (ECM).
B. Certain event codes may derate engine power. Monitor the diagnostic codes on Cat ET. Check for active diagnostic codes and logged codes (intermittent problems).
Note: Wait at least 30 seconds in order for diagnostic codes to become active.
Codes
Result: A code is active or logged.
Repair: Troubleshoot any codes before continuing with this procedure.
Verify that the repair eliminated the problem.
Result: A code is not active or logged.
Proceed to Test Step 2.
2. Cold Mode
A. Use Cat ET to verify that the engine has exited cold mode. Cold mode operation may slow throttle response.
If the engine is operating in cold mode, an indicator will be displayed on the top of any of the status screen.
Note: Although a sensors signal may be in the operational range of the sensor, certain failure modes of a sensor may produce an output signal that does not represent an accurate measurement. Use Cat ET to check that the pressures and the temperatures are fluctuating normally. Also check that the values are reasonable for the conditions that are present.
Cold Mode
Result: The engine is not operating in cold mode.
Proceed to Test Step 3.
Result: The engine has not exited from the cold mode.
Repair: This is normal operation. Return the engine to service.
3. Ensure that the latest Flash File Software is installed in the ECM
A. Use Cat ET to verify that the correct flash file is being used.
Flash File
Result: The latest flash file is installed.
Proceed to Test Step 4.
Result: The latest flash file is not installed.
Repair: Perform the following procedure.
1. Download the latest flash file from SIS Web.
2. Install the software into the ECM.
Refer to Troubleshooting, "ECM Software - Install for additional information".
4. Check for an Intermittent Throttle Signal
A. Monitor the status for "Throttle Position" on Cat ET.
B. Verify that the status for "Throttle Position" is stable and that the engine is able to reach high idle speed.
Throttle Signal
Result: The status for "Throttle Position" is stable.
Proceed to Test Step 5.
Result: The status for "Throttle Position" is not stable.
Repair: Make the necessary repairs. Refer to the appropriate diagnostic functional test for your application:
- Troubleshooting, "Throttle Position Sensor Circuit - Test"
- Troubleshooting, "Throttle Switch Circuit - Test"
- Troubleshooting, "Speed Control - Test"
Verify that the repair eliminated the problem.
5. Monitor the Decelerator Pedal
A. Monitor the decelerator pedal on Cat ET.
Decelerator Pedal
Result: Verify that the decelerator pedal is operating properly.
Repair: Refer to Troubleshooting,"Deceleration Position Sensor Circuit - Test" for the proper troubleshooting procedure.
If the problem is not resolved, proceed to Test Step 6.
6. Injection Actuation Pressure
If service has recently been performed on the engine, air may be present in the injection actuation pressure circuit. Allow the engine to fully warm