75533 Mercruiser SPRING

with the signal from the module for engine oil pressure and engine coolant temperature.Test Step 1. Check the Voltage At the Status Control Module (SCM)
Measure the voltage between terminal 3 and terminal 4 at the SCM.
Turn the main disconnect switch to the OFF position.
Disconnect the 3-pin connector at the module for the pressure and temperature.
Turn the main disconnect switch to the ON position.
Measure the voltage between terminal 3 and terminal 4 at the SCM.Expected Result:The voltage is between 11 VDC and 15 VDC for both measurements.Results:
OK - The voltage is between 11 VDC and 15 VDC for both measurements. Proceed to Test Step 2.
Not OK - The voltage is above 20 VDC for both measurements.Repair: Replace the SCM. Troubleshoot the module for the pressure and temperature. If necessary, replace the module.Verify that the repair eliminates the problem.STOP
Not OK - The voltage is between 15 VDC and 20 VDC for both measurements.Repair: Replace the SCM. Verify that the repair eliminates the problem.STOP
Not OK - The voltage is below 11 VDC for both measurements.Repair: Replace the SCM. Verify that the repair eliminates the problem.STOP
Not OK - The voltage is below 11 VDC for the first measurement. The voltage is between 11 VDC and 15 VDC for the second measurement.Repair: Replace the module for the pressure and temperature. Verify that the repair eliminates the problem.STOPTest Step 2. Check the Voltage At the SCM With the +Battery Wire Disconnected from Terminal 4 of the SCM
Measure the voltage between terminal 3 and terminal 4 at the SCM.
Turn the main disconnect switch to the OFF position.
Disconnect the wire from terminal 4 of the SCM.
Turn the main disconnect switch to the ON position.
Measure the voltage between terminals 3 and 4 at the SCM.Expected Result:The voltage is between 11 VDC and 15 VDC for both measurements.Results:
OK - The voltage is between 11 VDC and 15 VDC for both measurements. The power supply is OK. Proceed to Test step 3.
Not OK - The voltage is below 11 VDC before the wire at terminal 4 is disconnected and the voltage is between 11 VDC and 15 VDC after the wire at terminal 4 is disconnected.Repair: There is a problem with the −Battery circuit between the SCM and the module for the pressure and the temperature.Repair the connectors or wiring and/or replace the connectors or wiring. Verify that the repair eliminates the problem.STOP
Not OK - The voltage is above 15 VDC before the wire at terminal 4 is disconnected and the voltage is between 11 VDC and 15 VDC after the wire at terminal 4 is disconnected.Repair: There is a problem with the circuit between the SCM and the module for the pressure and the temperature.Repair the connectors or wiring and/or replace the connectors or wiring. Troubleshoot the module for the pressure and temperature. If necessary, replace the module.Verify that the repair eliminates the problem.STOPTest Step 3. Check the Voltage Between Terminal 5 and Terminal 3 At the SCM
Turn the main disconnect switch to the OFF position.
Return the wiring to the original configuration.
Turn the main disconnect switch to the ON position.
Measure the voltage between terminals 5 and 3 at the SCM.Expected Result:The voltage is between 4 VDC and 8 VDC.Results:
OK - The voltage is between 4 VDC and 8 VDC. The voltage is OK. Proceed to Test Step 4.
Not OK - The voltage is above 8 VDC. The voltage is not OK. Proceed to Test Step 5.
Not OK - The voltage is below 4 VDC.Repair: Disconnect the wire from terminal 5 of the SCM.If the voltage goes above 8 VDC, replace the module for the pressure and temperature.If the voltage remains the same, replace the SCM.Verify that the repair eliminates the problem.STOPTest Step 4. Check the 3-Pin Connector
Turn the main disconnect switch to the OFF position.
Return the wiring to the original configuration.
Disconnect the 3-pin connector from the module for the pressure and the temperature.
Disconnect the 3-pin harness from the SCM.
Measure the resistance between pin 1 of the connector for the module and the wire from terminal 4 of the SCM.
Measure the resistance between pin 2 of the connector for the module and the wire from terminal 3 of the SCM.
Measure the resistance between pin 3 of the connector for the module and the wire from terminal 5 of the SCM.Expected Result:The resistance measurements are less than 1 Ohm.Results:
OK - The resistance measurements are less than 1 Ohm. The harness is OK. Proceed to Test Step 5.
Not OK - At least one of the resistance measurements is more than 1 OHM.Repair: There is a problem with the harness.Repair the connectors or wiring and/or replace the connectors or wiring. Verify that the repair eliminates the problem.STOPTest Step 5. Check the Module for the Pressure and Temperature
Return the wiring to the original configuration.
At the module for the pressure and temperature, disconnect the 3-pin connector from the engine oil pressure sensor.
Turn the main disconnect switch to the ON position.
Measure the voltage between pin A and pin B on the harness connector.Expected Result:The voltage measurement is less than 4.5 VDC.Results:
OK - The voltage measurement is less than 4.5 VDC.Repair: Troubleshoot the harness between the pressure sensor and the module for the pressure and temperature.If necessary, repair the connectors or wiring and/or replace the connectors or wiring.If there is not a problem with the harness, replace the module for the pressure and temperature.Verify that the repair eliminates the problem.STOP
Not OK - The voltage measurement is greater than 6 VDC.Repair: Replace the module for the pressure and temperature. Troubleshoot the engine oil pressure sensor. If necessary, replace the sensor.Verify that the repair eliminates the problem.STOP