2. Turn the ignition on by turning the key to the "ON" (II) position.
3. Verify that the HDS is communicating with the vehicle and the ECM. If not, troubleshoot the DLC circuit.
4. Check if any DTCs are displayed on the screen. If a diagnostic trouble code (DTC) is present, diagnose and correct the cause of the problem before continuing with the test.
5. Turn the ignition key to the "OFF" position. Disconnect the 4P connector from the generator.
6. Start the engine and turn on the high beam headlights.
7. Measure the voltage between terminal No.2 of the generator 4P connector and the positive terminal of the battery.
Is there 1V or less voltage here?
- YES - go to step 11.
- NO - go to step 8.
8. Connect the SCS Service Test Signal circuit to the HDS, then turn the ignition switch to the "OFF" position.
Note: This action is necessary to prevent damage to the Engine Control Module (ECM).
9. Disconnect the 44P connector in the ECM unit.
10. Check for continuity between ECM connector terminal B41 and body ground.
Is the connection continuous?
- YES - Repair short in wire between generator and ECM.I
- NO - Update the ECM if it does not have the latest software, or temporarily substitute a known-good ECM, then retest. If the fault does not occur with a known-good ECM, replace the removed ECM.
11. Connect the SCS service test signal circuit to the HDS, then turn the ignition switch to the "OFF" position.
Note: This action is necessary to prevent damage to the Engine Control Module (ECM).
12. Disconnect the 44P connector in the ECM unit.
13. Check for continuity between terminal B41 of the ECM connector and terminal No.2 of the 4P generator connector.
Is the connection continuous?
- YES - replace the generator or repair it.
- NO - Repair open in wire between alternator and ECM.
(Information obtained from this source: hondabook)