Nissan Sentra Service Manual: On Board Diagnostic (OBD) System of Engine and CVT
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the driver of a malfunction causing emission deterioration.
CAUTION:
- Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. will cause the MIL to light up.
- Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease, dirt, bent terminals, etc.)
- Certain systems and components, especially those related to OBD, may use a new style slide-locking type harness connector. For description and how to disconnect, refer to PG-42, "Description".
- Be sure to route and secure the harnesses properly after work. The interference of the harness with a bracket, etc. may cause the MIL to light up due to the short circuit.
- Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system, etc.
- Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and TCM (Transmission control module) before returning the vehicle to the customer.
Precaution for Procedure without Cowl Top Cove.r.
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc to prevent damage to
windshield.
...
General Precautions
Always use a 12 volt battery as power source.
Do not attempt to disconnect battery cables while engine is
running.
Before connecting or disconnecting the ECM harness connector,
turn ignitio ...
Other materials:
Wiper and washer fuse
Description
Diagnosis procedure
1. Check fuses
Check that the following fuses are not blown.
Is the fuse blown?
Yes >> replace the blown fuse after repairing the affected circuit.
No >> inspection end. ...
Precautions when starting and driving
WARNING
Do not leave children or adults who
would normally require the assistance
of others alone in your vehicle. Pets
should also not be left alone. They
could accidentally injure themselves or
others through inadvertent operation of
the vehicle. Also, on hot, su ...
Before starting the engine
Make sure the area around the vehicle is
clear.
Check fluid levels such as engine oil, coolant,
brake and clutch fluid(if so equipped),
and windshield-washer fluid as frequently as
possible, or at least whenever you refuel.
Check that all windows and lights are clean.
Visually inspe ...
