The probable root causes are listed below:
- Vessel wiring
- Faulty switch
- Electronic Control Module (ECM)
- Faulty display indicator
Illustration 1 | g00774907 |
Dual Engine |
Check the wiring for the following problems: damage, abrasion, corrosion and incorrect attachments.
- Check the harness resistance from the ECM to the − Battery terminal.
- Turn the Engine Control Switch (ECS) to the "OFF" position. Disconnect the ECM connector P1 from the primary ECM and P1 from the secondary ECM.
- Put the synchronizing switch to the "Sync PORT" position.
- Measure the resistance from the primary ECM P1-19 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the secondary ECM P1-19 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the primary ECM P1-13 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the secondary ECM P1-13 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- Put the synchronizing switch to the "Sync Starboard" position.
- Measure the resistance from the primary ECM P1-19 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the secondary ECM P1-19 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the primary ECM P1-13 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the secondary ECM P1-13 to the − Battery terminal. The resistance should be less than 10 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- If the resistance measurements are correct, temporarily replace the ECM. Refer to Troubleshooting, "Replacing the ECM" before replacing the ECM. If the resistance measurements are incorrect, proceed to Test Step 3.
- Check the harness resistance between the 40-pin connector (port side) and the ECM.
- Put the synchronizing switch to the "Sync PORT" position.
- Disconnect the 40-pin connector (port side). Make a wire jumper that will extend from the 40-pin connector to the − Battery terminal.
- Connect one end of the wire jumper to the − Battery terminal. Connect the other end of the wire jumper to J3-2 on the 40-pin connector (port side).
- Measure the resistance from the primary ECM P1-19 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the secondary ECM P1-19 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the primary ECM P1-13 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the secondary ECM P1-13 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- Put the synchronizing switch to the "Sync Starboard" position.
- Remove the wire jumper from J3-2 of the 40-pin connector (port side). Connect the wire jumper to J3-1 of the 40-pin connector (port side).
- Measure the resistance from the primary ECM P1-19 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the secondary ECM P1-19 to the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the primary ECM P1-13 to the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance from the secondary ECM P1-13 to the − Battery terminal. The resistance should be less than 10 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- If the resistance is within the range, proceed to Test Step 4. If the resistance is incorrect, repair the harness between the 40-pin connector (port side) and the ECM.
- Check the Throttle Synchronization Switch for continuity.
- Put the synchronizing switch to the "Sync PORT" position.
- Measure the resistance between pin-3 and pin-4 on the synchronizing switch. The resistance should be less than 10 Ohms.
- Measure the resistance between pin-3 on the synchronizing switch and the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance between pin-2 on the synchronizing switch and P3-2 on the 40-pin connector (port side). The resistance should be less than 10 Ohms.
- Measure the resistance between pin-5 on the synchronizing switch and P3-1 on the 40-pin connector (port side). The resistance should be less than 10 Ohms.
- Put the synchronizing switch in the "Sync PORT" position. Measure the resistance between pin-3 and pin-2 on the synchronizing switch. The resistance should be less than 10 Ohms.
- Measure the resistance between pin-5 and pin-4 on the synchronizing switch. The resistance should be greater than 20,000 Ohms.
- Put the synchronizing switch in the "Sync Starboard" position. Measure the resistance between pin-3 and pin-2 on the synchronizing switch. The resistance should be greater than 20,000 Ohms.
- Measure the resistance between pin-5 and pin-4 on the synchronizing switch. The resistance should be less than 10 Ohms.
- If the resistance measurements are incorrect, repair the harness and/or the synchronizing switch. If the resistance is within the range, proceed to Test Step 5.
- Check the harness resistance between the 25-pin engine connector P3B and the ECM.
- Disconnect the 25-pin engine connector "P3B". Make a wire jumper that will extend from the 25-pin engine connector "P3B" to the − Battery terminal. Connect one end of the wire jumper on the − Battery terminal. Connect the other end of the wire jumper on P3B-8 of the 25-pin engine connector "P3B".
- Measure the resistance between the primary ECM P1-19 and the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance between the secondary ECM P1-19 and the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance between the primary ECM P1-13 and the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance between the secondary ECM P1-13 and the − Battery terminal. The resistance should be greater than 20,000 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- Remove the wire jumper from P3B-8 of the 25-pin engine connector "B". Insert the jumper onto P3B-10 of the 25-pin engine connector "B".
- Measure the resistance between the primary ECM P1-19 and the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the secondary ECM P1-19 and the − Battery terminal. The resistance should be greater than 20,000 Ohms.
- Measure the resistance from the primary ECM P1-13 and the − Battery terminal. The resistance should be less than 10 Ohms.
- Measure the resistance between the secondary ECM P1-13 and the − Battery terminal. The resistance should be less than 10 Ohms.
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
- If the resistance is within the range, proceed to Test Step 6. If the resistance is incorrect, repair the wiring between the 25-pin engine connector "P3B" and the ECM.
- Check the resistance of the harness between the 25-pin engine connector and the 40-pin connector (port side).
- Turn the ECS to the "OFF" position. Disconnect the 25-pin engine connector. Disconnect the 40-pin connector (port side).
- Measure the following resistances between the 25-pin engine connector and the 40-pin connector (port side):
- J3B-10 to J3-7
- J3B-8 to J3-2
Note: Wiggle the harness during the measurements in order to reveal an intermittent condition.
The resistance should be less than 10 Ohms through the harness.
- If the resistance is greater than 10 Ohms, then there is an open circuit in the harness. Repair the harness or replace the harness.