2001/06/01 Caterpillar

Engines: EPG

3508 (S/N: 3LS; 3PS; 3TS; 5XM)

3508B (S/N: 2HW; 4GM; 5KW; BGX; CNB)

3512 (S/N: 3MS; 3RS; 3WS; 6PM)

3512B (S/N: 4AW; 5AW; 6GW; 6WN; 8RM; BLF; BRK; CMC)

3516 (S/N: 3NS; 3SS; 3XS; 7KM)

3516B (S/N: 1NW; 2JW; 3EW; 6HN; 7RN; 8NW; BMB; BPJ; CPA; FDN)

Power Modules:

PM3508 (S/N: BLM; BPY)

PM3512 (S/N: BNR; BRF)

PM3516 (S/N: BPD; CAC)

Updated software is available for the engine Electronic Control Module (ECM) for the above listed engines. This software contains several new features and several improvements to existing strategies.

Refer to one of the cross-references for flash files that are published in the Service Information System (SIS) or the FIND system in order to determine the correct numbers for flash files that are for a particular engine. To use the FIND system, type "FLASH" in the "Search Document Types" field. Then type "3500B" in the "Key Word/Phrase" field. This search should return the following documents:

• 3500B Commercial Engine (Built > 4/97) FLASH File Cross-Reference

• 3500B Commercial Engine (Built < 4/97) FLASH File Cross-Reference

• 3500 With EUI Option Commercial Engine FLASH File Cross-Reference

• 3500B HD (High Displacement) Commercial Engine FLASH File Cross-Reference

• 3500B Machine Engine FLASH File Cross-Reference

Use the appropriate document to look up the flash file for a particular engine.

In the SIS, all the above cross-references for flash files are grouped into a single file that is called "readxref.txt". You can download this file and you can open this file with a word processor.

The cross-references for the flash files will be updated as files become available. The FIND system has the most current information. The SIS is updated periodically with information from the FIND system. Currently, the "FLASH File Part Number Progression" application in the TMI system does not provide accurate data for 3500 Engines.

SOFTWARE CHANGES

Software Changes

All of the following changes are included in the software for engines that were built after April 1997 that contain the D version of the electronics. Only the "Low Coolant Temperature Warning" change was added to the software for the engines that were built prior to April 1997 that contain the C version of the electronics. The 3.2 version or a latter version of the Cat ET is required to access some of the new parameters for this software.

Diagnostics Indicate An Incorrect Signal From A Fuel Pressure Sensor

The above listed engines may log "94-02 and/or 289-02 An Incorrect Signal from a Fuel Pressure Sensor" diagnostic codes mistakenly. A previous software release disabled these diagnostics when engine speed was less than 200 RPM. The previous software release reduced the problem, but the software release did not eliminate the problem.

This strategy has been improved in order to eliminate the false logging. The trip point for the diagnostic codes has been changed from 15 kPa (2 psi) differential pressure to 70 kPa (10 psi). This change will help prevent the incorrect fault logging, but this change will delay the notification of an "Incorrect Signal from a Fuel Pressure Sensor" problem until the differential pressure exceeds 70 kPa (10 psi).

In addition, the absolute value of the fuel filter differential pressure is now used for display and for logging events. This change will allow the monitoring of the pressure differential, even if the sensors are incorrectly installed.

Low Coolant Temperature Warning

This feature is intended to detect an overcooling condition such as stuck open coolant temperature regulators. Events that indicated low coolant temperature were logged by previous software versions during normal engine operating conditions. This commonly occurred when the engine was lightly loaded in cold weather. This resulted in nuisance alarms.

This strategy has been improved in order to reduce low coolant temperature warnings when the engine is lightly loaded. The strategy now uses the engine load and the coolant temperature in order to determine if the engine is being overcooled.

The new strategy averages the load over a ten minute period. If the average load is above a customer programmable value the low coolant temperature warning is enabled. The warning will be disabled if the average load drops below the programmed set point.

The calculation that determines the average load does not begin until the engine has been operating for 10 minutes. Therefore, the monitoring of low coolant temperature will not be activated during the first 10 minutes of operation regardless of engine load.

A new parameter "Coolant Warning Engine Load Enable Threshold" has been added in order to support this feature. This new parameter will be used in forthcoming versions of Cat ET. Currently, the parameter is identified as "Load Warning Set".

This set point for the percent load should be programmed to match the needs of the engine application. Ambient operating temperatures and typical load cycles of the engine should be considered when you are determining an appropriate value for this parameter.

Power Correction, Full Load Setting (FLS) and Full Torque Setting (FTS)

This programmable parameter is being added in order to adjust the fuel delivery at peak torque and rated engine speeds. This will normally be used in the factory after horsepower has been measured with a dynamometer. The programmable parameter will allow the factory to reduce the variations in the horsepower between engines.

The FLS and the FTS default to "not programmed" on a blank ECM. An active diagnostic code 268-02 is generated when the FLS or the FTS is not programmed. A factory level security password is required to change the FLS and the FTS. The FLS and the FTS may be programmed without passwords one time on a new ECM. This occurs when the tattletale is zero.

The correction for the duration of the fuel injection is limited to ± 5%. This parameter should not be used to increase the fuel delivery in order to compensate for problems in the installation and/or mechanical problems with the engine .

Annunciation For Altitude Derate

The "!Stop" light on the module for the EMS will now flash for 15 seconds when an altitude derate is active. After 15 seconds, the light will stop flashing. Former versions of the software annunciated an altitude derate continuously.

The engine altitude derate is not affected or disabled by this change. The length of time for the annunciation of an altitude derate is the only change. Because the engines were being intentionally operated at high altitudes in the derate mode by many customers, this change to the software was made. These customers do not need to see a "!Stop" light that is continuously flashing.

Calibration For The Injector Trim Codes

Previous versions of the software did not check in order to ensure that the injector trim codes were entered into the calibration screen for the Cat ET. The new software checks for this condition. The new software will activate a "1495-02 Injector Trim Not Prog" diagnostic code if the injector trim codes have never been programmed.