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:
P0122, P0123 TP Sensor
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0122 or P0123 is displayed with DTC P0643, first perform the
trouble diagnosis for DTC P0643.
Refer to EC-353, "DTC Logic".
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible caus ...
Parking, license plate and tail
lamps are not turned on
Description
The parking, license plate and tail lamps do not turn on in with any lighting
switch setting.
Diagnosis procedure
1.Combination switch (lighting and turn signal switch) inspection
Check the combination switch (lighting and turn signal switch). Refer to
BCS-72, "Symptom Table ...
Car phone or CB radio
When installing a CB, ham radio or car phone in
your vehicle, be sure to observe the following
precautions; otherwise, the new equipment may
adversely affect the engine control system and
other electronic parts.
WARNING
A cellular phone should not be used for
any purpose while dr ...
