Step 1. Verification
Step 2. Isolation
Step 3. Repair
Step 4. Recheck
- Identify what is the trouble and confirm the car for the occurrence of car trouble.
- After the car trouble is identified and confirmed verify if the condition is abnormal.
- Identify if there are other related function and circuit that is not working or working abnormally.
- Identify if there are related functions and circuit that is working normally.
Step 2. Isolation
- Using the manual intended for the car, locate the wiring diagrams and the schematic diagrams of the car with trouble.
- Using the wiring diagrams identify if the circuit is controlled by a switch, controlled by a relay or controlled by Electronic Circuit Module (ECM).
- Identify if the components that are on the same parallel circuit is working normally according to its functions.
- Identify if every component that is located on the same series circuit is working normally according to its functions.
- When doing a test on the circuits, use a test point where it can be accessed quickly and easily during testing.
- Follow the most logical process when making a decision.
- All of the relay circuits must be separated and then test individually the field coil and contact point circuits.
- Bench test every component, supply power and ground on each component to verify their operations if the components are working properly.
- Take note that the power source must have sufficient voltage, the load must always be operating properly in good condition and that the ground is with sufficient current capacity.
Step 3. Repair
- The first thing to do is to fix the harness and clean all the connections.
- Replace the components that are malfunctioned and repair what causes the failure of the circuits.
Step 4. Recheck
- Verify and confirm if the car trouble has been resolved and that all of the related circuits and components are working properly.
- Verify and confirm that there are no other problems were incurred during the repair.
