859769R 1 Mercury SERVICE MANUAL

Table 1
Diagnostic Codes Table    
Code and Description    Conditions which Generate this Code    System Response    
105-3 Engine Intake Manifold #1 Temperature : Voltage Above Normal     The Electronic Control Module (ECM) detects a signal voltage that is more than 4.95 VDC for ten seconds.     The code is logged.
The amber warning lamp is illuminated.
The service tool displays "Error Indicator" on the status screen for this parameter.    
105-4 Engine Intake Manifold #1 Temperature : Voltage Below Normal     The ECM detects a signal voltage that is less than 0.2 VDC for eight seconds.    
110-3 Engine Coolant Temperature : Voltage Above Normal     The ECM detects a signal voltage that is more than 4.95 VDC for ten seconds.     The code is logged.
The amber warning lamp is illuminated.
The service tool displays "Error Indicator" on the status screen for this parameter.    
110-4 Engine Coolant Temperature : Voltage Below Normal     The ECM detects a signal voltage that is less than 0.2 VDC for eight seconds.    
175-3 Engine Oil Temperature 1 : Voltage Above Normal     The ECM detects a signal voltage that is more than 4.95 VDC for ten seconds.     The code is logged.
The amber warning lamp is illuminated.
The service tool displays "Error Indicator" on the status screen for this parameter.    
175-4 Engine Oil Temperature 1 : Voltage Below Normal     The ECM detects a signal voltage that is less than 0.2 VDC for eight seconds.    
Illustration 1 g01961988
Schematic for the passive analog sensorSystem OperationUse this procedure to troubleshoot any suspect problems with the temperature sensors for the engine.The sensor signal for the passive sensor is routed from the ECM to terminal 1 of the sensor connector. The sensor return for the passive sensors is routed from the ECM to terminal 2 of the sensor connector.The most likely cause of a code is a problem with an electrical connector or wiring. The least likely cause of a code is the ECM.
Illustration 2 g01962016
Locations of the passive analog sensor (left side engine view) (1) Engine coolant temperature sensor (2) Intake manifold air temperature sensor (3) Engine oil temperature sensor
Illustration 3 g01962019
Locations of the connectors at the ECM (right front engine view) (4) J2/P2 ECM connectors
Illustration 4 g01962021
Terminal locations at the P2 ECM connector for the passive analog sensors (P2-36) Engine oil temperature (P2-39) Analog return (P2-42) Intake manifold air temperature (P2-43) Engine coolant temperature
Illustration 5 g01436505
Terminal locations at the connector for the passive analog sensor (Terminal 1) Sensor signal (Terminal 2) Analog sensor return
Table 2
Troubleshooting Test Steps    Values    Results    
1. Check for Active Diagnostic Codes and Check for Logged Diagnostic Codes
A. Connect Caterpillar Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the "Product Status Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
C. Monitor the active diagnostic code screen on Cat ET. Record any active diagnostic codes.
Note. Wait at least 30 seconds in order for diagnostic codes to become active.
   
Logged Diagnostic Codes
Or
Active Diagnostic Codes
   
Results: A diagnostic code is logged but is not active.
Repair: Do not troubleshoot a logged code unless the code relates to an operator complaint. If the code is logged and the code does not relate to an operator complaint, clear the code.
If the logged code relates to this procedure, inspect the electrical connectors and the wiring for the circuit.
Refer to Troubleshooting, "Electrical Connectors - Inspect"
Results: A -3 diagnostic code is active.
Proceed to Test Step 2.
Results: A -4 diagnostic code is active.
Proceed to Test Step 6.    
2. Inspect the Electrical Connectors and the Wiring
A. Check the harness and the wiring for abrasion and for pinch points.
B. Thoroughly inspect all connectors that are in the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect " for details.
   
-3 code
   
Results: The connectors and wiring are OK.
Proceed to Test Step 3.
Results: The connectors and/or wiring are NOT OK.
Repair: Repair the connectors or wiring and/or replace the connectors or wiring.
   
3. Check for Battery Voltage on the Signal Wire
A. At the sensor harness connector, measure the voltage between the signal terminal and the return terminal.
B. Record the result.
   
-3 code
(+) Battery voltage    
Results: The voltage is OK. The voltage measurement is less than the +Battery voltage. The signal wire is not shorted to the +Battery.
Proceed to Test Step 4.
Note: The following Results: will cause a -3 code.
Results: The voltage is NOT OK. The voltage measurement is approximately the +Battery voltage. The signal wire is shorted to the +Battery.
Repair: Repair the wiring, when possible. Replace parts, if necessary. Verify that the problem is resolved.
   
4. Determine if the Sensor has an Open Circuit Condition by Creating a Short Circuit at the Sensor Connector
A. Using appropriate terminals, fabricate a jumper wire.
B. At the sensor harness connector, connect the signal terminal and the return terminal with the jumper wire. The jumper will replace the sensor with a short circuit.
Note. Wait at least 30 seconds in order for the diagnostic codes to become active.
C. Record the resulting diagnostic code.
   
-3 Code    
Results: A -3 diagnostic code is active when the connector is disconnected. A -4 diagnostic c