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 Codes
All trouble codes are 2-digit numbers. PCM outputs codes one digit at a time. These codes indicate current faults in system and should be serviced in order of appearance. See TROUBLE CODE REFERENCE under CIRCUIT TESTS to find correct CIRCUIT TEST.
Scan tester, if used, will count pulses and display them as a digital code. If using MIL, trouble codes are displayed as light pulses from CHECK ENGINE light. When using MIL, pay attention to length of pauses in order codes correctly. See Fig 1 . Pass Codes
Code 55 indicates system passes that portion of test. If Code 55 is not retrieved, proceed to CIRCUIT TEST corresponding with trouble code that is output.
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.