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:
B terminal circuit
Description
“B” terminal circuit supplies power to charge the battery and to operate the
vehicles electrical system.
Diagnosis procedure
Regarding wiring diagram information. Refer to chg-9, "wiring diagram".
1.Check “b” terminal connection
Turn ignition switc ...
C1142 Press sensor
DTC Logic
DTC DETECTION LOGIC
DTC
Display Item
Malfunction detected condition
Possible causes
C1142
PRESS SEN CIRCUIT
When a malfunction is detected in master cylinder
pressure sensor.
Stop lamp switch system
ABS actuator and electric unit
(co ...
Description
NOTICE:
Trouble diagnoses indicate work procedures required to diagnose problems
effectively. Observe the following
instructions before diagnosing.
Before performing trouble diagnoses, read the “Work Flow” in each
section.
After repairs, re-check that the problem has been comp ...
