Nissan Sentra Service Manual: 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 ignition switch OFF and disconnect negative battery
cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
- Before removing parts, turn ignition switch OFF and then disconnect
battery ground cable.

- Do not disassemble ECM
- If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is disconnected.
However, this is not an indication of a malfunction.
Do not replace parts because of a slight variation.
- If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values

- When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
- Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) voltage
to develop in coil and condenser, thus resulting in damage
to ICs.
- Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to prevent engine control system malfunctions
due to receiving external noise, degraded operation
of ICs, etc.
- Keep engine control system parts and harness dry.


- After performing each TROUBLE DIAGNOSIS, perform DTC
CONFIRMATION PROCEDURE or Component Function
Check. The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Component Function
Check should be a good result if the repair is completed.


- Do not operate fuel pump when there is no fuel in lines.
- Tighten fuel hose clamps to the specified torque.
- Do not depress accelerator pedal when starting.
- Immediately after starting, do not rev up engine unnecessarily.
- Do not rev up engine just prior to shutdown.

- When installing C.B. ham radio or a mobile phone, be sure to
observe the following as it may adversely affect electronic
control systems depending on installation location.

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 th ...
Special Service Tools
NOTE:
The actual shapes of Kent-Moore tools may differ from those of special
service tools illustrated here.
Commercial Service Tools
...
Other materials:
Diagnosis system (BCM)
Common item
Common item : consult function (bcm - common item)
Application item
Consult performs the following functions via can communication with bcm.
System application
Bcm can perform the following functions.
Intelligent key
Intelligent key : consult function (bcm - intelligent ke ...
Diagnosis system (TCM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1 Trip Detection Diagnosis and 2 Trip Detection
Diagnosis
NOTE:
“Start the engine and turn OFF the ignition switch after warm-up.” This is
defined as 1 trip.
TRIP DETECTION DIAGNOSIS
When initial malfunction is detected, TCM mem ...
Control buttons
The control buttons for the Bluetooth® Hands-
Free Phone System are located on the steering
wheel.
PHONE/SEND
Press the button to initiate
a VR session or answer an incoming
call.
You can also use the button
to interrupt the system feedback
and give a command at once. See
“List of ...
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