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:
B0091 Front side air bag satellite sensor LH
Description
DTC B0091 FRONT SATELLITE SENSOR LH
The front side air bag satellite sensor LH is wired to the air bag diagnosis
sensor unit. The air bag diagnosis
sensor unit will monitor the front side air bag satellite sensor LH for internal
failures and its circuits for communication
errors. ...
Precaution
Precaution for supplemental restraint system (srs) "air bag" and "seat
belt pre-tensioner"
The supplemental restraint system such as “air bag” and “seat belt pre-tensioner”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
Diagnosis system (BCM) (with intelligent key system)
Common item
COMMON ITEM : CONSULT Function (BCM - COMMON ITEM)
APPLICATION ITEM
CONSULT performs the following functions via CAN communication with BCM.
Direct Diagnostic Mode
Description
ECU identification
The BCM part number is displayed.
Self Diagnostic Result
...
