38344 Mercruiser WASHER, ALTERNATOR BRACKET SCREW

Table 1
Diagnostic Codes Table    
J1939 Code and Description    Conditions which Generate this Code    System Response    
1180-3
Engine Turbocharger 2 Turbine Inlet Temperature : Voltage Above Normal     The ECM detects a duty cycle that is greater than 96 percent for ten seconds.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
1180-4
Engine Turbocharger 2 Turbine Inlet Temperature : Voltage Below Normal     The ECM detects a duty cycle that is less than 4 percent for ten seconds.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
1180-8
Engine Turbocharger 2 Turbine Inlet Temperature : Abnormal Frequency, Pulse Width, or Period     The ECM detects a sensor frequency that is greater than 600 Hz or less than 400 Hz.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
1181-3
Engine Turbocharger 1 Turbine Inlet Temperature : Voltage Above Normal     The ECM detects a duty cycle that is greater than 96 percent for ten seconds.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
1181-4
Engine Turbocharger 1 Turbine Inlet Temperature : Voltage Below Normal     The ECM detects a duty cycle that is less than 4 percent for ten seconds.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
1181-8
Engine Turbocharger 1 Turbine Inlet Temperature : Abnormal Frequency, Pulse Width, or Period     The ECM detects a sensor frequency that is greater than 600 Hz or less than 400 Hz.     The code is logged.
If the signal from the other exhaust temperature sensor is OK, the signal from that sensor is used. If the signal from the other exhaust temperature sensor is not OK, a default value is used.    
2452-8
Generator Total Real Power : Abnormal Frequency, Pulse Width, or Period     The ECM detects a sensor frequency that is greater than 600 Hz or less than 400 Hz.     The code is logged.
Gas substitution shuts off.    System OperationUse this procedure to troubleshoot any suspect problems with the sensor for the left turbocharger turbine inlet temperature or the right turbocharger turbine inlet temperature.The Pulse Width Modulated Sensor (PWM) provides a signal to the ECM. The PWM signal is used to represent certain engine operating conditions. The sensors receive 8.0 0.4 VDC from a regulated power supply.The ECM performs an automatic calibration of these sensors whenever the ECM is powered and the engine has been off for at least 5 seconds.The ECM provides short circuit protection for the internal power supply. A short circuit to the battery will not damage the internal power supply.The following components can cause problems with the power supply:
Electrical connector or wiring
Sensor
ECMThe most likely cause of a problem is a problem with an electrical connector or wiring. The least likely cause is a problem with the ECM.
Illustration 1 g03658061
PWM sensor schematic
Illustration 2 g03658067
P1 ECM connector (P1-4) Digital supply (P1-5) Digital return (P1-18) Digital return
Illustration 3 g03658069
P2 ECM connector (P2-65) Right-hand turbocharger turbine inlet temperature (P2-73) Left-hand turbocharger turbine inlet temperature
Illustration 4 g01159881
Terminal locations at the connectors for the exhaust temperature sensor (Terminal A) Digital sensor supply (Terminal B) Digital return (Terminal C) Signal
Table 2
Troubleshooting Test Steps    Values    Results    
1. Check for Active Codes and Logged Codes
A. Connect Caterpillar Electronic Technician (ET) to the service tool connector.
B. Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes.
Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
C. Determine if a diagnostic code has occurred several times.
Note: A diagnostic code that is logged several times is an indication of an intermittent problem. Most intermittent problems are the result of a bad connection between a socket and a pin in a connector. There could also be a bad connection between a wire and a terminal.
D. Look for one or more of the following diagnostic codes that are active or logged:
- 1181-3
- 1181-4
- 1181-8
- 1180-3
- 1180-4
- 1180-8
   
Codes    
Result: A code is not active or logged.
Repair: There may be an intermittent problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct procedures for inspecting electrical connectors.
Result: A code is active or logged.
The ECM detects a problem in one of the circuits for the exhaust temperature sensors.
Proceed to Test Step 2.
   
2. Check the Digital Supply Voltage at the Sensor Connector
A. Turn the main disconnect switch to the OFF position.
B. Disconnect the suspect sensor at the sensor connector.
C. Restore the electrical power to the ECM.
D. Measure the supply voltage on the harness side of the sensor connector. Measure the voltage between terminal A and terminal B for the suspect sensor.
   
8.0 0.4 VDC    
Result: The supply voltage is 8.0 0.4 VDC. The supply voltage is reaching the sensor connector.
Proceed to Test Step 4.
Result: The supply voltage is not 8.0 0.4 VDC. The supply voltage is not reaching the sensor connector.
Proceed to Test Step 3.
   
3. Check the Digital Supply Voltage at the ECM
A. Turn the main disconnect switch to the OFF position.
B. Disconnect the J2/P2 and the J1/P1 ECM connectors.
C. Fabricate a jumper wire that is long enough