3176C, 3196 & 3406E MARINE ENGINES Caterpillar

Section 1: Electronic System Overview

Usage:

System Operations

The 3176C/3196 and 3406E Marine Engines utilizes Electronic Unit Injectors. These injectors are mechanically actuated and electronically energized. The injector solenoid is mounted on top of the injector body along side the rocker and return spring.

Electronic Controls

The 3176C/3196 and 3406E Marine Engines electronic system consists of the Electronic Control Module (ECM) and engine sensors. The ECM is the computer which controls the engine operating parameters. The Personality Module in the ECM contains the software which controls how the ECM behaves (the personality module stores the operating maps that define power, torque curves, rpm, etc). The injection pump, fuel lines and fuel injection nozzles used in mechanical engines have been replaced with an electronic unit injector in each cylinder. A solenoid on each injector controls the amount of fuel delivered by the injector. The Electronic Control Module (ECM) sends a signal to each injector solenoid to provide complete control of the engine.

Engine Governor

The Electronic Control on the engine serve as the engine governor. The Electronic Control determines when and how much fuel to deliver to the cylinders based on the actual and desired conditions at any given time.

The governor uses the Throttle Position Sensor to determine the desired engine rpm and compares this to the actual engine rpm determined through the Engine Speed/Timing Sensor. If desired engine rpm is greater than the actual engine rpm, the governor injects more fuel to increase engine rpm.

Timing Considerations

Once the governor has determined how much fuel is required, it must next determine when to inject the fuel. Injection timing is determined by the ECM after considering input from the Coolant Temperature Sensor, Inlet Air Manifold, Temperature Sensor, Atmospheric Pressure Sensor, And Inlet Air Manifold (Boost) Pressure Sensor.

The ECM determines where top center on cylinder number one is located from the Engine Speed/Timing Sensor signal. The ECM decides when injection should occur relative to top center and provides the signal to the injector at the desired time. The ECM adjusts timing for best engine performance, fuel economy and white smoke control. Actual or Desired Timing cannot be viewed with an Electronic Service Tool.

Fuel Injection

The ECM controls the amount of fuel injected by varying signals to the injectors. The injectors will pump fuel only if the injector solenoid is energized. The ECM sends a high voltage signal to energize the solenoid. By controlling the timing and duration of the high voltage signal, the ECM can control injection timing and the amount of fuel injected.

The Personality Module inside the ECM sets certain limits on the amount of fuel that can be injected. FRC Fuel Pos is a limit based on boost pressure to control the air/fuel ratio for emissions control. When the ECM senses a higher boost pressure (more air into cylinder), it increases the FRC Fuel Pos limit (allows more fuel into cylinder). Rated Fuel Pos is a limit based on the power rating of the engine and rpm. It is similar to the rack stops and torque spring on a mechanically governed engine. It provides power and torque curves for a specific engine family and rating. All of these limits are determined at the factory in the Personality Module and cannot be changed.

Figure 1.1 - Fuel Injection

Customer Parameters Effect on Engine Governing

A unique feature with Electronic Engines is the Customer Specified Parameters. These parameters allow the engine owner to fine tune the ECM for engine operation to accommodate the typical or specific usage of the engine.

Many of the Customer Parameters provide additional restrictions on the action the ECM will take in response to the operators' input. For example, the Top Engine Limit is an rpm limit the ECM uses as a maximum rpm for fuel delivery to the injectors. The ECM will not fuel the injectors above this rpm.

Some parameters are intended to notify the operator of potential engine damage such as Engine Monitoring Parameters. Other parameters are provided to enhance the engine installation or provide engine operating information to the engine owner.

Engine Monitoring

Caterpillar provides a factory installed Engine Monitoring System. The Caterpillar Engine Monitoring System monitors engine oil pressure, coolant temperature, inlet air manifold, air temperature, coolant level, fuel temperature and fuel pressure.

Caterpillar Engine Monitoring can be programmed to different modes (OFF, WARNING and DERATE). The Coolant Temperature Sensor, Oil Pressure Sensor and Coolant Level Sensor (if enabled) will operate in the Engine Monitoring Mode selected.

For example, if DERATE was selected, the engine will derate engine power if the Coolant Temperature Sensor, Oil Pressure Sensor or Coolant Level Sensor (if enabled) detect conditions exceeding acceptable limits. The Warning Lamp/Alarm will be ON.

Caterpillar Engine Monitoring OFF Operation

If Caterpillar Engine Monitoring is programmed to OFF, the ECM will not flag any of the sensor values and disables those diagnostics associated with Engine Monitoring even though the level or conditions are exceeded which could cause the ECM to take Engine Monitoring action.

The ECM still uses these sensors for normal engine operation, such as the Coolant Temperature Sensor for Cold Mode operation.

Caterpillar Engine Monitoring WARNING Operation

If the system is programmed to WARNING, the ECM turns on the Warning Lamp and logs the event to indicate a problem has been detected by the Engine Monitoring System. No further ECM or engine action occurs if the ECM is programmed to WARNING.

NOTE: The Oil Pressure Sensor can not be programmed to WARNING, while the Coolant Temperature Sensor operates in a DERATE mode.

Caterpillar Engine Monitoring DERATE Operation

If the system is programmed to DERATE, the ECM begins by flashing or activating the Warning Lamp. If the problem is due to a Low Coolant Level, Low Oil Pressure, High Inlet Air Manifold Temperature, High Coolant Temperature or High Fuel Temperature condition, the ECM will turn the Warning Lamp ON.

When Very Low Oil Pressure, Very Low Coolant Level, or a High or Very High Coolant Temperature are detected, DERATE Mode begins by flashing the Warning Lamp. Whenever the Warning Lamp is flashing, the ECM is limiting (derating) the engine power.

For High and Very High Coolant Temperature, or Very Low Coolant Level, the ECM reduces available power. If the detected condition is Very Low Oil Pressure, power and engine rpm are limited. This derating of engine performance is provided to the operators so action can be taken to avoid engine damage.

Figure 1.2 - Engine Monitoring Oil Pressure Graph

Figure 1.3 - Engine Monitoring Coolant Temperature Graph

Figure 1.4 - Engine Monitoring Coolant Level Graph

Figure 1.5 - 3176C/3196 Very Low Oil Pressure Graph

Figure 1.6 - 3406E Very Low Oil Pressure

Figure 1.7 - Engine Monitoring Coolant Level Time Graph

Self-Diagnostics

The electronic system has some ability to diagnose itself. When a problem is detected, a diagnostic code is generated and the Diagnostic Lamp is turned ON and/or the Warning Lamp/Alarm is turned ON. In most cases, the code is also stored in permanent memory (Logged) in the ECM.

Diagnostic Fault Codes

When diagnostic codes occur, they are called Active. They indicate a problem of some kind currently exists. They should always be serviced first. If the engine has an Active Code, find the code in the Quick Reference Sheet For Diagnostic Code at the beginning of this manual of in Section 4: Troubleshooting With A Diagnostic Code and proceed to the appropriate Functional Test section to diagnose the cause. Diagnostic codes stored in memory are Logged. Since the problem may have been temporary or may have been repaired since the time it was logged, logged codes do not necessarily mean something needs to be repaired. They are meant to be an indicator of probable causes for intermittent problems. Some of the codes require passwords to clear. Codes not requiring passwords to clear are automatically deleted from memory after 100 engine operating hours.

Operating Information Stored in the ECM

The ECM uses a second battery connection to maintain a portion of memory used for Engine Operating Data when the keyswitch is OFF (ECM is not powered). Disconnecting this line does not affect the ECM stored Factory/Customer Parameters, or logged diagnostic codes. Interrupting this connection causes the ECM to lose some portion of the engine operating information, or trip information as explained in the following paragraphs.

Lifetime Totals Stored In The ECM

The ECM maintains engine total data for the following parameters:

Engine Hours is engine running hours (it does not include time when the ECM is powered ON without the engine running).

Idle Hours and Idle Fuel can include time when the engine is not operating under load. Fuel Information can be displayed in US gallons or liters.

Average Load Factor provides relative engine operation (how hard the engine has been operated compared to the maximum), and is determined using Maximum Fuel (maximum fuel the engine can use during operation), Idle Fuel, and the Fuel Used. All of these parameters are available using an Electronic Service Tool within the Trip Data menu.

NOTE: The ECM accumulates the Total Data in memory dependent on the Unswitched +Battery connection.

When the data reaches 2 hours (time parameters) or 150 liters (40 US gallons) for fuel used parameters, the ECM transfers this quantity to permanent memory. This means if you disconnect ECM Connector J1/P1 (disconnecting the Unswitched +Battery connection), the ECM Totals may vary by as much as one-half of these values [1 hour or 75 liters (20 US gallons)], but no more.

When the ECM detects a loss of the Unswitched +Battery connection it automatically increments the memory dependent upon the Unswitched +Battery connection to one-half of the value that could be lost. This reduces the margin of error from a maximum of 2 hours to 1 hour and 150 to 75 liters (40 to 20 US gallons).

This means disconnecting the Unswitched +Battery line can actually increase these Totals. If the value in the Unswitched +Battery memory before disconnection was less than the automatic increment the total will be increased. If an ECM is replaced the Data Totals can be transferred to the new ECM using an Electronic Service Tool.

Trip Data Stored In The ECM

Trip data allows the owner of the vessel to track engine operation over owner defined intervals. Trip Data includes Engine Hours, Fuel Consumption, Idle Time, Idle Fuel, the percent of Idle Time and the Average Load Factor.

Two types of data are stored in the ECM, Engine Data and Operation Histogram Data. Data can be reset at any time with an Electronic Service Tool. The data is stored in memory maintained through the Unswitched +Battery connection when the keyswitch is OFF. Disconnecting the Unswitched +Battery line will reset or clear this data.

Histograms

The Engine Speed (RPM) Histogram records engine operation time spent in engine rpm ranges from 600 rpm to above 2400 rpm (in 100 rpm increments). The Electronic Service Tool calculates the percentage of time spent in each of the engine rpm ranges.

The Load Factor Histogram records operation from 0 to 100 percent in 10 percent increments using the same parameters as Engine Speed Histograms.

A reset of the Histograms can be done with an Electronic Service Tool (may require Customer Passwords).

Maintenance Indicator Data

The ECM records the Lifetime Data Totals when a maintenance reset occurs for three levels of maintenance - PM1, PM2, and Coolant Flush/Fill. The previous maintenance point is used by the ECM to calculate when the next maintenance is due. The Maintenance Indicator feature is programmable to hours or fuel consumption. The PM1 maintenance is programmable to OFF, Automatic-Hours, Manual-Hours, Automatic-Fuel or Manual-Fuel.

If PM1 is programmed to automatic, the ECM calculates the next maintenance due by considering the unit operation history from the previous maintenance interval. If the unit has a history of poor fuel economy, the maintenance indicator will occur sooner than a unit with better fuel economy.

The ECM also uses the Engine Oil Capacity, with a larger capacity providing a longer maintenance interval. Engine Oil Capacity is programmed in quarts (or liters). If the PM1 Maintenance Indicator is programmed to Manual, the owner can program in their own specific maintenance interval. PM2 and Coolant Flush/Fill intervals are determined by the factory.

Programmable Parameters

Certain parameters that affect 3176C/3196 Marine Engine operation may be changed with the Electronic Service Tools. The parameters are stored in the ECM and are protected from unauthorized changes by passwords. These parameters are either "System Configuration Parameters" or "Customer Parameters".

System Configuration Parameters are set at the factory and effect emissions or power ratings within a family of engines. Factor Passwords must be obtained and used to change System Configuration Parameters.

Customer Parameters are variable and can be used to affect speed limits, rpm/power ratings within the limits set by the factory. Customer Passwords are necessary to change Customer Specified Parameters.

Some parameters may affect engine operation in ways a operator does not expect. Without adequate training, these parameters may lead to power or performance complaints, even when the engine is performing to specification.

Read Section 2: Programming Parameters for more details.

Passwords

"System Configuration Parameters" are protected by Factory Passwords. Factory passwords are calculated on a computer system available only to Caterpillar dealers. Since factory passwords contain alphabetic characters, only an ECAP or Caterpillar Electronic Technician may change System Configuration Parameters. System Configuration Parameters affect power family or emissions.

"Customer Parameters" are protected by Customer Passwords. The customer passwords are programmed by the customer.

See section Section 2: Programming Parameters for more details when passwords are needed and how to obtain them.

Service Tools

The Caterpillar Electronic Service Tools for the electronic control system are designed to help the service technician analyze and locate faults or problems within the system. It is required to perform some sensor calibrations electronically, and to read or change engine parameters.

The Electronic Control Analyzer Programmer (ECAP) tool has small plug-in modules, called Service Program Modules (SPM), to adapt the basic tool to the specific Caterpillar electronic control application.

Caterpillar Electronic Technician (ET) requires a personal computer with the ET software installed and a Caterpillar Communication Adapter to translate from the CAT Data Line to the computer RS-232 protocol.

The ECAP or ET communicates with the Electronic Control Module to read diagnostic codes, to read the various sensor output signals such as engine rpm, or boost pressure, and controls electronic calibration of the sensors through the ECM.

There are several adapter cables, Breakout T cables, probes, etc, that are used with the Electronic Service Tools in order to access measurements of signals.

The Breakout T harness is inserted in series between a harness jack and plug to permit voltage measurement on an operating system. The Bypass T harness is used to bypass the harness signal lines for engine sensors.

A heavy duty multimeter is suitable for making the necessary adjustments. Other Special Tools include those needed to measure pressure or temperature.

ECAP Parts Required

Connecting ECAP Electronic Service Tool

The Electronic Control Analyzer & Programmer (ECAP) and the Communications Adapter are DC powered from the engine or unit battery source.

Use the following procedures to connect the ECAP to the Service Tool data link Connector.

1. Turn the keyswitch to the OFF position.

2. Connect the Electronic Service Tool to the electronic system through the data link connector, J60 (or J42, if equipped) to the 139-4166 harness connector cable.

3. Connect the opposite end of the adapter cable to the Electronic Service Tool. Turn the keyswitch to the ON position to begin testing. The Electronic Service Tool will operate with the engine running (keyswitch ON) or with the engine off (keyswitch ON). If the Electronic Service Tool does not communicate with the ECM, Refer to Section 3 P307: Electronic Service Tool Will Not Communicate With ECM.

NOTE: The Electronic Service Tool may restart during engine cranking due to a voltage dip on the battery line.

Connecting ET Electronic Service Tool and Communication Adapter Tool

ET consists of an IBM compatible computer (laptop) and software. The software allows the laptop user to program ECM parameters, read and display sensor values and switches, perform diagnostic tests and calibrate sensors. The following table outlines the tools required to use ET.

The Communication Adapter Tool uses DC power from the battery. Use the following procedure to connect ET and the Communication Adapter service tools to the engine.

1. Turn the keyswitch to the OFF position.

2. Connect the 139-4166 cable between the Engine Service Tool Connector J60 (or if equipped J42) and the Communication Adapter CONTROL Connector.

3. Connect the 7X1425 cable between the laptop RS-232 serial port and the Communication Adapter SERVICE Connector.

4. Turn the keyswitch to the ON position, engine OFF. This will provide Battery voltage to the ECM. ET and the Communication Adapter Tool will operate with or without the engine running. If ET and Communication Adapter Tool do not communicate with the ECM, Refer to Section 3 P-307: Electronic Service Tool Will Not Communicate With ECM.

Optional Service Tools

Figure 1.8 - Service Tools

3176C & 3196 SENSOR AND CONNECTOR LOCATIONS

Figure 1.9 - 3176C & 3196 Sensor and Connector Locations

3406E SENSOR AND CONNECTOR LOCATION

Figure 1.10 - 3406E Sensor and Connector Locations

Connector Diagram

Figure 1.11 - Connector Views

Figure 1.12 - Block Diagram

Service Information Report

After verifying the correct repair has been performed on the vessel it is important to provide concise, detailed information to Caterpillar. This information helps Caterpillar better serve you and the Customer.

Recommendations

Provide a copy of the "Customer Questionnaire" located on in Section 3: Troubleshooting Without A Diagnostic Code in this manual. Include comments for the Customer's Complaint section of the report indicating if the Warning Lamp/Alarm was on continuously or intermittently and if symptoms such as low power are present.

Failure Cause

Comments on Failure cause should include the number of diagnostic codes that were logged and if the code was Active. Indicate the source of the problem and how it was discovered, such as followed procedure P-514, or a visual inspection revealed wire abrasion on the engine harness.