Nissan Maxima Service and Repair Manual: 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 injury to the
driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage
front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment,
and may only deploy one front
air bag, depending on the severity of a collision and whether the front
occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB
section of this Service Manual.
WARNING:
- To avoid rendering the SRS inoperative, which could increase
the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all
maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
- Improper maintenance, including incorrect removal and
installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of
Spiral Cable and Air Bag
Module, see the SR section.
- Do not use electrical test equipment on any circuit related to
the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or
orange harnesses or harness
connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
- When working near the Airbag Diagnosis Sensor Unit or other
Airbag System sensors with the Ignition
ON or engine running, DO NOT use air or electric power tools or strike near
the sensor(s) with a
hammer. Heavy vibration could activate the sensor(s) and deploy the air
bag(s), possibly causing
serious injury. When using air or electric power tools or hammers, always
switch the Ignition OFF, disconnect the
battery and wait at least three minutes before performing any service.
On Board Diagnostic (OBD) System of Engine and CVT
The ECM has an on board diagnostic system. It will illuminate the malfunction
indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
- Always 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 illuminate.
- Always to connect and lock the connectors securely after work.
A loose (unlocked) connector will
cause the MIL to illuminate due to the open circuit. (Always 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-57, "Description".
- Always to route and secure the harnesses properly after work.
The interference of the harness with a
bracket, etc. may cause the MIL to illuminate due to the short circuit.
- Always to connect rubber tubes properly after work. A
misconnected or disconnected rubber tube
may cause the MIL to illuminate due to the malfunction of the EVAP system or
fuel injection system,
etc.
- Always to erase the unnecessary malfunction information
(repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the
customer.
General Precautions
- Always use a 12 volt battery as power source.
- Never 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.
- Never 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. Thus, engine
operation can vary slightly in
this case. However, this is not an indication of a malfunction. Never
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 ECM harness connector, fasten (B) it
securely with a lever (1) as far as it will go as shown in the figure.
2 : ECM
A : Loosen
- When connecting or disconnecting pin connectors into or
from ECM, never damage pin terminals (bends or break).
Check 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.
- Before replacing ECM, perform ECM Terminals and Reference
Value inspection and check ECM functions properly. Refer to
EC-522, "Reference Value".
- Handle mass air flow sensor carefully to avoid damage.
- Never clean mass air flow sensor with any type of detergent.
- Never disassemble electric throttle control actuator.
- Even a slight leakage in the air intake system can cause serious
incidents.
- Never shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
- When measuring ECM signals with a circuit tester, never allow
the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
- Never use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the
ground.
- B1 indicates bank 1, B2 indicates bank 2 as shown in the figure.
- Never operate fuel pump when there is no fuel in lines.
- Tighten fuel hose clamps to the specified torque.
- Never depress accelerator pedal when starting.
- Immediately after starting, never rev up engine unnecessarily.
- Never 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.
Description
FUEL CUT CONTROL (AT NO LOAD AND HIGH ENGINE SPEED)
If the engine speed is above 2,000 rpm under no load (for example, the
selector lever position is P or N and
engine speed is over ...
Special Service Tools
The actual shapes of Kent-Moore tools may differ from those of special
service tools illustrated here.
Commercial Service Tools
...
Other materials:
Key cylinder switch
Description
The main power window and door lock/unlock switch detects condition of the
door key cylinder switch and
transmits to BCM as the LOCK or UNLOCK signal.
Component Function Check
1. CHECK DOOR KEY CYLINDER SWITCH INPUT SIGNAL
Check KEY CYL UN-SW, KEY CYL UN-SW in "DATA MONITOR" mod ...
Under the hood and vehicle
The maintenance items listed here should be
checked periodically (for example, each time you
check the engine oil or refuel).
Battery*: Check the fluid level in each cell. The
fluid should be at the bottom of the filler opening.
Vehicles operated in high temperatures or under
severe condit ...
Combination switch reading system
System Diagram
System Description
OUTLINE
BCM reads the status of the combination switch (light, turn
signal, wiper and washer) and recognizes the status of each switch.
BCM has a combination of 5 output terminals (OUTPUT 1 - 5) and 5
input terminals (INPUT 1 - 5) and reads a maximum ...