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:
FM/AM radio with compact disc (CD) player (if so equipped)
CD eject button
CD insert slot
SCAN button
DISP button
RPT/RDM button
TUNE/FOLDER knob / MENU button
AUX IN jack
AUX button
CD button
AM button
FM button
VOL (volume) control knob
/ (power) button
Station select (1 - 6) buttons
TRACK button
SEEK button
For ...
P1650 Starter motor relay 2
Description
ECM controls ON/OFF state of the starter relay, according to the engine and
vehicle condition. ECM transmits
a control signal to IPDM E/R via BCM by CAN communication.
Under normal conditions, ECM controls and maintains the starter relay in OFF
state during following condition:
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Diagnosis system (ECM)
Diagnosis description : 1st trip detection
logic and two trip detection logic
When a malfunction is detected for the first time, 1st trip DTC and 1st trip
Freeze Frame data are stored in the
ECM memory. The MIL will not illuminate at this stage. <1st trip>
If the same malfunction is dete ...
