| Fault code No. | 43 |
| Symptom | Incorrect voltage supplied to the fuel injector and fuel pump |
| Fail-safe action | Engine startup: Possible |
| Riding: Possible | |
| Diagnostic monitoring code No. | D:50 |
| Meter display | Approximately 12.0 |
| Checking method | Set the engine stop switch to "q", and then compare with the actually measured battery voltage. (If the battery voltage is lower, perform recharging.) |
| Item/components and probable cause | Check or maintenance job | Sensor inspection procedure | |
| 1 | Connection of relay unit coupler. Check the connection of the coupler is secure. Remove the coupler, and check each pin (for bending, wear, or locking). | Poor connection → Connect it securely, or repair/replace the wire harness. | Start and idle the engine for approximately 30 seconds. Then, check the fault code indication. No fault indicated. → Recovered. Fault code indicated. → Check the next step. |
| 2 | Connection of main harness ECU coupler. Check the connection of the coupler is secure. Remove the coupler, and check each pin (for bending, wear, or locking). | Poor connection → Connect it securely, or repair/replace the wire harness. | Start and idle the engine for approximately 30 seconds. Then, check the fault code indication. No fault indicated. → Recovered. Fault code indicated. → Check the next step. |
| 3 | Continuity of wire harness between the battery, relay unit, ECU and fuel injectors coupler | Open or short circuit → Replace the wire harness. Red-Red Red/Blue-Red/Blue | Start and idle the engine for approximately 30 seconds. Then, check the fault code indication. No fault code indicated. → Recovered. Fault code indicated. → Check the next step. |
| 4 | Fuel injection system relay malfunction | Check in the diagnostic mode (Code No. 50). No operation sound of fuel injection system relay is heard. → Replace the relay unit. | Start and idle the engine for approximately 30 seconds. Then, check the fault code indication. No fault code indicated. → Recovered. Fault code indicated. → Check the next step. |
| 5 | ECU malfunction | Replace the ECU. |