Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Reading Trouble Codes
Warm engine to normal operating temperature and turn ignition off. Ensure engine speed is below 4000 RPM while warming up engine. Connect digital code tester to vehicle. See Figure . Start engine and wait 3 minutes.
If a code is displayed, check for cause of fault using instructions outlined under DIAGNOSTIC PROCEDURE . If there is more than one fault in system, the lowest numbered code will be displayed first. If ignition is turned off after a fault has occurred, the malfunction code will not be displayed by tester.
| Code | Circuit Affected |
|---|---|
| 1 | Ignition Pulse |
| 2 | Airflow Meter |
| 3 | Coolant Thermo Sensor |
| 4 | Intake Air Temperature Sensor |
| 5 | Feedback System |
| 6 | Throttle Position Sensor |
| 8 | EGR Position Sensor (Turbo) |
| 9 | Atmospheric Pressure Sensor |
| 21 | Atmospheric Pressure Sensor (Turbo) |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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