3176B MARINE ENGINE ELECTRONIC CONTROL SYSTEM INCLUDES COMPUTERIZE Caterpillar

The throttle position sensor (TPS) eliminates the mechanical throttle and governor linkages (along with their inherent adjustments). The TPS utilizes operator lever movement and sends an electrical signal to the engine Electronic Control Module (ECM). The TPS signal, along with the speed/timing signal is processed by the ECM to control precise engine speed.

Connecting Throttle Position Sensor

Single Engine Installation

Throttle Position Sensor Connection Schematic.

1. Connect (+)Battery Bus Bar to Pin-A of the Throttle Position Sensor connector.

2. Connect (-)Battery Bus Bar to Pin-B of the Throttle Position Sensor connector.

3. Connect Pin-37 of the J1 Customer Connector to Pin-C of the Throttle Position Sensor connector.

NOTE: Pin-C is the throttle output of the TPS and is a Pulse Width Modulated signal (PWM) indicating throttle position. Programmed engine location will default for single engine installation.

Connecting Backup Throttle Position Sensor

Single Engine Installation

1. Connect (-)Battery Bus Bar through the Secondary Throttle Enable Switch to Pin-2 (Secondary Throttle Enable) of the J1 Customer connector.

2. Connect (+)Battery Pin-6 of the J1 Customer connector to Pin-1 of Terminal Strip 1.

3. Connect Pin-2 of Terminal Strip 1 to Pin-A of the Secondary Throttle Position Sensor.

4. Connect Pin-3 of Terminal Strip 1 to Pin-A of the Primary Throttle Position Sensor.

5. Connect (-)Battery Pin-5 of J1 Customer Connector to Pin-1 of Terminal Strip 2.

6. Connect Pin-2 of Terminal Strip 2 to Pin-B of the Primary Throttle Position Sensor.

7. Connect Pin-3 of Terminal Strip 2 to Pin-B of the Secondary Throttle Position Sensor.

8. Connect Pin-37 (Primary Throttle) of J1 Customer Connector to Pin-C of Primary Throttle Position Sensor.

9. Connect Pin-31 (Secondary Throttle) of J1 Customer connector to Pin-C of Secondary Throttle Position Sensor.

10. Mechanically link the two throttle position sensors. Calibrate the throttle position sensors.

NOTE: Refer to Calibrate the Throttle Position Sensor in this guide or see SENR6500 Electronic Troubleshooting Manual (from SENR6505 Service Manual) and SEHS9199 Tool Operating Manual for NEXG4516 Marine Engine Functions Service Program Module (SPM). Programmed engine location will default for single engine installation. Ensure that the engine location is programmed into the ECM with the ECAP.

Connecting the PORT and STBD Throttle WITHOUT Engine Synchronization

Two Engine Installation

9X9647 Throttle Position Sensor Dimensions

Refer to General Dimension drawing provided with the engine or see your Caterpillar dealer.

Connecting the PORT and STBD Primary Throttle Position Sensors (TPS) Without Engine Synchronization

STBD Throttle Schematic

PORT Throttle Schematic

1. Connect (+)Battery Bus Bar to Pin-A of the Throttle Position Sensor connector.

2. Connect (-)Battery Bus Bar to Pin-B of the Throttle Position Sensor connector.

3. Connect Pin-37 of the J1 Customer Connector to Pin-C of the Throttle Position Sensor connector.

NOTE: Pin-C is the throttle output of the PORT and/or STBD TPS and is a Pulse Width Modulated Signal (PWM) indicating throttle position.

Throttle and Engine Synchronization System

The purpose of engine synchronization is to link the electronic controls of both engines to a single throttle.

This feature adds operator convenience, vessel control, and is a standard practice in marine applications to provide for either throttle to be used in a back-up situation.

The operator can use a switch to transfer the control of two or more engines to a single throttle lever. The Electronic Control Module (ECM) will then control the engine speed from the master throttle lever. Engine synchronization can be transferred to either the PORT or STARBOARD throttle.

Connecting the PORT and STBD Throttle WITH Engine Synchronization

Two Engine Installation - Primary and Secondary Throttle Inputs Synchronization System.

Starboard (STBD)

1. Connect Pin-C of the STBD throttle position sensor to Pin-1 of the STBD terminal strip.

2. Connect Pin-2 of the STBD terminal strip to Pin-31 (Secondary Throttle) of the PORT J1 Customer Connector.

3. Connect Pin-3 of the STBD terminal strip to Pin-37 (STDB Primary Throttle) of the STBD J1 Customer Connector.

4. Connect Pin-A of the STBD TPS to Pin-6 (+)Battery of the STBD J1 Customer Connector.

5. Connect Pin-B of the STBD TPS to Pin-5 (-)Battery Bus Bar of the STBD J1 Customer Connector.

PORT

6. Connect Pin-C of the PORT throttle position sensor to Pin-1 of the PORT terminal strip.

7. Connect Pin-2 of the PORT terminal strip to Pin-31 (Secondary Throttle) of the STBD J1 Customer Connector.

8. Connect Pin-3 of the PORT terminal strip to Pin-37 (PORT Primary Throttle) of the PORT J1 Customer Connector.

9. Connect Pin-A of the PORT TPS to Pin-6 (+)Battery of the PORT J1 Customer Connector.

10. Connect Pin-B of the PORT TPS to Pin-5 (-)Battery Bus Bar of the PORT J1 Customer Connector.

Connecting the Synchronization Switch

1. Connect Pin-23 (Synchronize Input 1) of the STBD J1 Customer Connector to Pin-2 of the synchronization switch.

2. Connect Pin-2 (Synchronize Input 2) of the PORT J1 Customer Connector to Pin-2 of the synchronization switch.

3. Connect Pin-2 (Synchronize Input 2) of the STBD J1 Customer Connector to Pin-5 of the synchronization switch.

4. Connect Pin-23 (Synchronize Input 1) of the PORT J1 Customer Connector to Pin-5 of the synchronization switch.

5. Connect (+) Battery to Pin-1 of the Synch Switch and Pin-6 of the Synch Switch.

6. Connect (-)Battery Bus Bar to Pin-3 of the Synch Switch and Pin-4 of the Synch Switch.

7. Calibrate Throttle Position Sensors.

Throttle Position Sensor Calibration and Linkage Adjustment

Calibrate Throttle Position Sensor

Refer to Throttle Position Sensor Calibration and Adjustment in the SENR6500 Electronic Troubleshooting Manual (from SENR6505 Service Manual) to aid OEM installation. Programmed engine location will default for single engine installation. Ensure that the engine location is programmed into the ECM with the ECAP.

Programming Engine Location

If you are using Caterpillar provided engine synchronization, the Caterpillar Electronic Control Analyzer Programmer (ECAP) Service Tool can be used to program engine location (PORT, STBD or CENTER). Refer to SENR6500 Electronic Troubleshooting Manual (from SENR6505 Service Manual) and SEHS9199 Tool Operating Manual for NEXG4516 Marine Engine Functions Service Program Module (SPM) for additional information.

Inspect Throttle Linkage

Inspect the throttle linkage for loose, bent, broken, missing, or worn components. Also, inspect for interference with the linkage or return spring.

The throttle linkage should work smoothly without excessive drag, and return to LOW IDLE position WITHOUT assistance in less than one second.

Linkage Adjustment At Low Idle Position (Minimum Throttle)

Example of display.

The calibration of the throttle position sensor requires the use of an 8T8697 Electronic Control Analyzer Programmer (ECAP). Use the SENR6500 Electronic Troubleshooting Manual (from SENR6505 Service Manual) and SEHS9199 Tool Operating Manual for NEXG4516 Marine Engine Functions Service Program Module (SPM) for additional information.

* Turn ignition key to the OFF position.

* Connect to the ECAP.

* Turn ignition key to the ON position with the engine OFF.

* Access the Monitor Throttle Position Sensor Signal screen on the ECAP to display the Duty Cycle.

Adjust the throttle linkage, with the throttle at LOW IDLE position, until the Duty Cycle reading (display) is between eight and ten percent.

NOTE: After adjustment, a slight movement away from the LOW IDLE linkage stop should increase the Duty Cycle reading.

Linkage adjustment for Throttle Position Sensor.

When properly adjusted, the rotary disc should be positioned as shown when the throttle is in the LOW IDLE position.

Linkage Adjustment At High Idle Stop Position

Adjust the throttle linkage, with the throttle at HIGH IDLE stop position, until the Duty Cycle reading (display) is between 90 and 93 percent.

When properly adjusted, the rotary disc should be positioned as shown when the throttle is in the HIGH IDLE stop position.

Repeat Adjustment At Low Idle Position (Minimum Throttle)

NOTE: On some linkage designs, changing the HIGH IDLE adjustment can affect the LOW IDLE adjustment.

Repeat the Adjustment At Low Idle Position procedures to verify that the LOW IDLE stop is still properly adjusted.

Connecting Throttles With Engine Synchronization For Three Engine Installation

Three engine installation with engine synchronization.

Connecting Throttles With Engine Synchronization For Four Engine Installation

Four engine installation with engine synchronization.