3126B Petroleum Engine Caterpillar

Event codes alert the operator that an abnormal engine operating condition such as low oil pressure or high coolant temperature has been detected. When the event code is generated, the event is active.

Active Event Codes

An active event code represents a problem with engine operation. Correct the problem as soon as possible.

Active event codes are listed in ascending numerical order. The code with the lowest number is listed first.

When certain event codes are activated, the Electronic Control Module (ECM) also generates a flash code that will be displayed on the diagnostic lamp. Refer to Troubleshooting, "Diagnostic Code Cross Reference" for a cross-reference between event codes and flash codes.

Illustration 1 is an example of the operating range of an oil temperature sensor. Do not use the Illustration to troubleshoot the oil temperature sensor.

Illustration 1	g01139661
Example of the typical operating range of an oil temperature sensor (1) This area represents the normal temperature range for the engine oil. The normal output voltage of the sensor is between 0.2 VDC and 4.2 VDC. (2) In this area, the oil temperature above 107 °C (225 °F) is higher than normal. The output voltage of the sensor will generate an event code. The sensor does not have an electronic problem. (3) In these areas, the output voltage of the sensor is too high or too low. The voltage is outside of the normal range. The electronic problem will generate a diagnostic code. Refer to Troubleshooting, "Troubleshooting with a Diagnostic Code" for additional information on diagnostic codes.

The following format is used for event codes:

"EXXX (Y) Description of the event"

The "E" means that the code is an event code. The "XXX" represents a numeric identifier for the event code. The "(Y)" represents a numeric identifier for the severity of the event. This is followed by a description of the event. Refer to the following example:

"E004 (3) Engine Overspeed Shutdown"

In this example, the number 3 indicates the severity of the event. The ECM has three levels of response to events:

Warning (1) - This condition represents a serious problem with engine operation. However, this condition does not require a derate or a shutdown.

Derate (2) - For this condition, the ECM reduces the engine's power in order to help prevent possible engine damage.

Shutdown (3) - For this condition, the ECM shuts down the engine in order to help prevent possible engine damage.

Responses to certain events may be programmed into the ECM. Refer to Troubleshooting, "System Configuration Parameters".

Logged Event Codes

When the ECM generates an event code the ECM logs the code in permanent memory. The ECM has an internal diagnostic clock. The ECM will record the following information when an event code is generated:

• The hour of the first occurrence of the code

• The hour of the last occurrence of the code

• The number of occurrences of the code

Logged events are listed in chronological order. The most recent event code is listed first.

This information can be helpful for troubleshooting intermittent problems. Logged codes can also be used to review the performance of the engine.

Clearing Event Codes

A code is cleared from memory when one of the following conditions occur:

• The code does not recur for 100 hours.

• A new code is logged and there are already ten codes in memory. In this case, the oldest code is cleared.

• The service technician manually clears the code.

Always clear logged event codes after investigating and correcting the problem which generated the code.

Troubleshooting

For basic troubleshooting of the engine, perform the following steps in order to diagnose a malfunction:

1. Obtain the following information about the complaint from the operator:
   • The event and the time of the event

   • Determine the conditions for the event. The conditions will include the engine rpm and the load.

   • Determine if there are any systems that were installed by the dealer or by the customer that could cause the event.

   • Determine whether any additional events occurred.

2. Verify that the complaint is not due to normal engine operation. Verify that the complaint is not due to error of the operator.

3. Narrow the probable cause. Consider the operator information, the conditions of operation, and the history of the engine.

4. Perform a visual inspection. Inspect the following items:
   • Fuel supply

   • Oil level

   • Oil supply

   • Wiring

   • Connectors

Be sure to check the connectors. This is very important for problems that are intermittent. Refer to Troubleshooting, "Electrical Connectors - Inspect".

If these steps do not resolve the problem, identify the procedures in this manual that best describe the event. Check each probable cause according to the tests that are recommended.