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.
Entering & Exiting Diagnostic Mode
To enter diagnostic mode, use scan tool. With ignition on and engine off, connect a scan tool to Data Link Connector (DLC) located behind left side of dash. See Fig 1. The Diesel Electronic Control (DEC)/electronically-controlled transmission systems will enter diagnostic mode. In this mode, PCM will display DTCs on scan tool. Refer to scan tool instructions provided by manufacturer for further information. To exit diagnostic mode, turn ignition off and remove scan tool from DLC.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.