3508, 3508B, 3508C, 3512, 3512B, 3512C, 3516, 3516B and 3516C Engines Caterpillar Monitoring System Caterpillar

Note: Ensure that the desired diagnostic code (CID FMI) is on hold. Ensure that the "SERV CODE" indicator is ON. Find the connector contact that is located on the Main Display Module. The electrical system schematic for the engine that is being serviced may assist the operator in finding the connector contact that corresponds to the current CID that is shown.

The diagnostic code is recorded when the Main Display Module reads a signal that is from the sensor that is abnormal. The signal is not identifiable to the input circuits of the Main Display Module. As a result of this diagnostic condition, the corresponding Indicator Lamp will flash and the Gauge Needle will be located in the warning region. The following examples are possible causes.

• The sensor for marine gear oil temperature has a problem.

• The ground circuit of the sensor for marine gear oil temperature that is located in the engine harness is open.

• The sensor of the signal circuit for marine gear oil temperature that is located in the engine harness is shorted to +battery.

• The sensor of the signal circuit for marine gear oil temperature that is located in the engine harness is open or the connector is disconnected.

• The Main Display Module has a problem.

1. Check the Display Area and the Harness.

   1. Turn the "ECS" switch to the OFF/RESET position.

   2. Check for loose terminal connections or corroded terminal connections to the sensor for marine gear oil temperature.

   3. Clean corroded terminals and tighten loose connections.

   4. Turn the "ECS" switch to the COOLDOWN/STOP position. The "SERV CODE" indicator should be ON for the diagnostic code CID 0177 FMI 08.

2. Confirm that the harness code selection matches the application.

   1. Determine the CURRENT harness code selection. For more information, see Testing And Adjusting, "Harness Code - Troubleshoot".

   2. Determine the CORRECT harness code selection for the application. For more information, see Systems Operation, "Quad Gauge Module".

   3. Compare the CURRENT harness code selection to the CORRECT harness code selection.

      Expected Result: The CURRENT harness code selection is correct for the application.

      Results:

      • OK - Proceed to 3.

      • Not OK - Correct the harness code selection or install marine gear sensors so that the application matches the current harness code selection. If the marine gear sensors are not installed, use harness code 11. If harness code 9, harness code 10 or harness code 12 is selected, make sure the marine gear sensors are installed. If the cause of the diagnostic is not found, proceed to 3.

3. Measure the Voltage of the Marine Gear Oil Temperature Sensor Supply Wire.

   1. Turn the "ECS" switch to the COOLDOWN/STOP position.

   2. Use the 7X-1710 Multimeter Probe to measure the voltage from the marine gear oil pressure sensor ground wire (pin B) to the supply wire (pin A).

      Expected Result: The voltage should be 8.0 ± 0.5 DCV.

      Results:

      • OK - The voltage is correct. Proceed to Step 4.

      • Not OK - The voltage is less than 0.5 DCV. The harness wiring has a problem. There is an open circuit, a short to ground in the supply wire of the sensor for marine gear oil pressure or a poor connection. Repair the harness or replace the harness. If the cause of the diagnostic fault is not found, proceed to Step 4.

4. Measure The Voltage of the Marine Gear Oil Temperature Signal.

   1. Turn the "ECS" switch to the COOLDOWN/STOP position.

   2. Use the 7X-1710 Multimeter Probe to measure the voltage from the Marine Gear Oil Pressure Sensor Ground Wire (pin B) to the Supply Wire (pin C).

      Expected Result: The voltage should be between 1.0 DCV and 7.0 DCV.

      Results:

      • OK - The signal voltage at the sensor is correct. Proceed to Step 5.

      • Not OK - The signal voltage at the sensor is not correct. If the voltage is greater than 7.0 DCV, proceed to Step 6. If the voltage is less than 1.0 DCV, proceed to Step 7.

5. Measure The Voltage of the Marine Gear Oil Temperature Signal Voltage.

   1. Turn the "ECS" switch to the "COOLDOWN/STOP" position.

   2. Use the 7X-1710 Multimeter Probe to measure the voltage from the ground wire of the Main Display Module (contact 2) to the signal wire (contact 28).

      Expected Results: The voltage should be equal to the voltage that was recorded in Step 4.

      Results:

      • OK - The voltage is correct. The Main Display Module is receiving a valid signal voltage. The Main Display Module has a problem. Replace the Main Display Module. See Testing And Adjusting, "Module - Replace" for more information.

      • Not OK - The voltage is not equal to the voltage that was measured in Step 4. The engine harness has an open circuit in the signal circuits or the ground circuits. Repair the engine harness or replace the engine harness.

6. Check For A Short To +Battery.

   1. Turn the "ECS" switch to the OFF/RESET position.

   2. Disconnect the connector of the Main Display Module and the connector of the Marine Gear Oil Temperature Sensor.

   3. Use the 7X-1710 Multimeter Probe to measure the resistance between +battery and the signal wire (pin C) for the Marine Gear Oil Temperature sensor.

      Expected Results: The resistance should be greater than 5000 ohms.

      Results:

      • OK - The resistance of the signal wire for the harness is correct. Replace the Main Display Module. For more information, see Testing And Adjusting, "Module - Replace".

      • Not OK - The resistance is less than 5000 ohms. Repair the harness or replace the harness.

7. Check For A Short To Ground.

   1. Turn the "ECS" switch to the OFF/RESET position.

   2. Disconnect the connector of the Main Display Module and the connector of the Marine Gear Oil Temperature Sensor .

   3. Use the 7X-1710 Multimeter Probe to measure the resistance that is between ground and the signal wire (pin C) for the Marine Gear Oil Temperature Sensor.

      Expected Result: The resistance should be greater than 5000 ohms.

      Results:

      • OK - The resistance of the signal wire for the harness is correct. Replace the Main Display Module. For more information, see Testing And Adjusting, "Module - Replace".

      • Not OK - The resistance is less than 5000 ohms. Repair the harness or replace the harness.