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.
1990 Nissan-Datsun Sentra BaseFACTORY OEM SERVICE PROCEDURE
Final Steps For All Code Charts
NOTE:
When code chart step indicates CHECK COMPONENT, see indicated component in SYSTEM/COMP TESTS
article.
Unless otherwise instructed in code chart, perform the following steps after repair:
- Reinstall any part removed.
- Erase the self-diagnostic memory.
- Ensure Code 55 (no malfunction) is displayed in self-diagnostic mode.
- Test drive vehicle.
- Perform self-diagnosis.
- If code resets, check for damage to ECU pin terminals and connector harness.
Factory Service Tools
Use the Manual With the Right Hardware
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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.