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.
Self-Diagnostic System: Description
There are several methods available to enter into self-diagnostics. Using either Nissan's CONSULT, Generic Scan Tool (GST) or Malfunction Indicator Light (MIL), review and record any DTC or freeze-frame information available before clearing DTCs or disconnecting the battery for a prolonged period.
Before entering self-diagnostics with MIL or GST, review the following precautions before proceeding:
- Review and record all stored DTCs before entering into diagnostic procedures.
- When ignition is turned off for more than 5 seconds during PCM Mode II, system will automatically return to Mode I.
- If battery is disconnected for an extended period, DTCs may be lost from memory.
- If battery is disconnected or DTCs cleared, SRT codes must be reset prior to performing an I/M test.
- Be careful not to erase stored DTCs before recording data for diagnostic testing.
- Switching mode selector on PCM from diagnostic test mode I to diagnostic test mode II is not possible when engine is running.
- Ensure PCM diagnostic test mode selector is turned back to the full counterclockwise position whenever vehicle is in use.
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.