Basic Inspection Procedure
Measuring Condition of Electronic Parts" Resistance
The measured resistance at high temperature after vehicle running may be high or low. So all resistance must be measured at ambient temperature (20°C, 68°F), unless stated otherwise.
Intermittent Problem Inspection Procedure
Sometimes the most difficult case in troubleshooting is when a problem symptom occurs but does not reoccur during test. An example would be if a problem appears only when the vehicle is cold but has not appeared when warm. In this case, the technician should thoroughly make out a "Customer Problem Analysis Sheet" and recreate (simulate) the environment and condition in which the vehicle was having the issue.
- Clear Diagnostic Trouble Code (DTC).
- Inspect all connections, check terminal for poor connections, loose wires, bent, broken or corroded pins, and then verify that the connectors are securely fastened at all times.
- Lightly shake the connector and wiring harness vertically and horizontally.
- Repair or replace the component with a problem.
- Perform road test to verify that the problem has disappeared.
- Simulating Vibration
- Sensors and Actuators
: Lightly shake sensors, actuators or relays by finger.
WARNING: Strong vibration may break sensors, actuators or relays. - Connectors and Harness
: Lightly shake the connector and wiring harness vertically and then horizontally.
- Simulating Heat
- Heat components suspected of causing the malfunction with a hair dryer or other heat source.
WARNING:- DO NOT heat components to the point of damaging them.
- DO NOT heat the ECM directly.
- Sensors and Actuators
- Simulating Water Sprinkling
- Sprinkle water onto vehicle to simulate a rainy day or a high humidity condition.
- Simulating Electrical Load
- Turn on all electrical systems to simulate an excessive electrical load (Radios, fans, lights, rear window defogger, etc.).