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:
SRS Air bag warning lamp does not turn OFF
Diagnosis Procedure
1.CHECK AIR BAG MODULE AND SEAT BELT PRE-TENSIONER
Check the deployment of air bag module.
Is air bag module deployed?
YES >> Replace the malfunctioning parts.
NO >> GO TO 2.
2.CHECK AIR BAG FUSE
Check 10 A fuse [No.3, located in fuse block (J/B)].
Is th ...
Symptom diagnosis
The sport mode indicator lamp does not turn on
Description
The sport mode indicator lamp does not turn on when the sport mode switch is
operated.
Diagnosis procedure
1.Perform combination meter on board diagnosis
Perform combination meter on board diagnosis. Refer to mwi-16, "descriptio ...
Abs branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch OFF.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the abs actuator and electric unit
(control unit) for damage, bend
and loose connection (unit side and connector side).
...
