994914 Volvo.Penta Hex. socket screw

Illustration 1 g00630930
The GSC+ communicates with the relay driver module (RDM) by a serial data link. When the data link malfunctions, R1 output (terminal 2 of the RDM) will be activated on and off at a rate of 0.5 Hz. Relays R2 through R9 may maintain the current state. Also, the relays may default to the OFF position. These steps are controlled by a jumper between terminals 6 and 7 of the RDM. If the jumper is present, R2 through R9 will default to OFF.Note: The maximum distance between a module and the GSC+ is 305 m (1000 ft). If this specification is not met, the data link may malfunction. The GSC+ may show a CID 475 fault. If the distance is not in compliance with the specification, shorten the distance between the RDM and the GSC+.Note: Faults are created when the harness connector is disconnected from the GSC+ during these troubleshooting procedures. Clear these created faults after the particular fault is corrected and the particular fault is cleared. In a properly operating system, when the harness connector is removed from the GSC+, the following diagnostic fault codes are recorded:CID 100 FMI 3 - Pressure Sensor (Engine Oil) CID 110 FMI 3 - Temperature Sensor (Engine Coolant)CID 111 FMI 3 - Fluid Level Sensor (Engine Coolant)CID 175 FMI 3 - Temperature Sensor (Engine Oil)CID 190 FMI 3 - Speed Sensor (Engine)CID 336 FMI 2 - Switch (Engine Control)The possible cause of a CID 475 FMI 3 is a short to the battery positive terminal.The GSC+ is not able to detect an open circuit condition on the relay driver module data link. Clear the fault from the fault log after the troubleshooting is complete.
Check The Voltage Of The Data Signal.
At the RDM, measure the DC voltage from terminal 4 (positive meter lead) to terminal 7 (negative meter lead).Expected Result: The voltage should change constantly. The range will vary from 0 DCV to 10 DCV.Results:
OK: The voltage measurement is correct. Proceed to Step 3.
NOT OK: The voltage measurement is NOT correct. Proceed to Step 2.
Check The Voltage Of The RDM And Check The Voltage Of The GSC+.
At the RDM, disconnect all wires from terminal 4.
Disconnect the harness connector from the GSC+.
At the RDM, measure the DC voltage from terminal 4 (positive meter lead) to terminal 7 (negative meter lead). Voltage should be 11.6 0.5 DCV.
Measure the DC voltage from contact 30 of the GSC+ to the battery negative terminal of the relay module. The relay module is located on the rear of the GSC+. The voltage should change constantly. The range of change is between 0 DCV to 5.5 DCV.Expected Result: For Step 2.c, the voltage should be 11.6 0.5 DCV. For Step 2.d, the voltage should change constantly. The range of change is between 0 DCV to 5.5 DCV.Results:
OK: Both voltage measurements are correct. Proceed to Step 3.
NOT OK: The voltage that was measured at the RDM (Step 2.c) is NOT correct. Replace the RDM. STOP.
NOT OK: The voltage that was measured at the GSC+ (Step 2.d) is NOT correct. Replace the GSC+. STOP.
Check For A "B+" Short In The Harness.
Disconnect the harness connector from the GSC+.
At the RDM, disconnect all wires from terminal 4.
Check the resistance between the wires on the terminal 4 and the relay module B+. The relay module is located on the rear of the GSC+.
Check the resistance between the wires on the terminal 4 and the relay module B-. The relay module is located on the rear of the GSC+.Expected Result: Both measurements (Step 3.c and Step 3.d) should be greater than 20000 ohms.Results:
OK: Both the resistance measurements are correct. Check the electrical connectors, terminals and wiring. See Testing And Adjusting, "Electrical Connector - Inspect". If the fault still exists after the inspection, replace the RDM. STOP.
NOT OK: Either one or both of the resistance measurements are NOT correct. The harness wiring with the incorrect measurement for resistance is shorted. Troubleshoot and repair the faulty harness wiring between the RDM and the GSC+. See the preceding System Schematic. STOP.