ROD AS 2494120 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the electrical system if a problem is suspected with an engine temperature sensor. Also, use this procedure if any one of the diagnostic codes in Table 1 is active or easily repeated.
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 10 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 8 seconds.
110-3 Engine Coolant Temperature : Voltage Above Normal The ECM detects a signal voltage that is more than 4.95 VDC for 10 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 8 seconds.
175-3 Engine Oil Temperature 1 : Voltage Above Normal The ECM detects a signal voltage that is more than 4.95 VDC for 10 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 8 seconds. System 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 1 g02683617
Schematic for the passive sensors
Illustration 2 g02683897
Locations of the passive analog sensor (right side engine view)
(1) Engine coolant temperature sensor
(2) Intake manifold air temperature sensor
(3) Engine oil temperature sensor
Illustration 3 g02683936
Locations of the connectors at the ECM control box (top side engine view)
(4) J2/P2 ECM connectors
(5) J1/P1 ECM connectors
(6) Engine harness connector (for non-incendive components)
Illustration 4 g02683998
Terminal locations at the P1 ECM connector for the passive sensors
(P1-26) Engine oil temperature
(P1-61) −Battery
(P1-63) −Battery
(P1-65) −Battery
(P1-67) −Battery
(P1-69) −Battery
Illustration 5 g02684004
Terminal locations at the P2 ECM connector for the passive analog sensors
(P2-84) Intake manifold air temperature
(P2-92) Engine oil temperature
Illustration 6 g01436505
Terminal locations at the connector for the passive analog sensor
(Terminal 1) Sensor signal
(Terminal 2) Analog sensor return Test Step 1. Check for Diagnostic Codes that are Active or Logged
Remove electrical power from the engine.
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Restore electrical power to the engine. Set the engine control to STOP.
Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes. Note: Wait at least 30 seconds in order