Infiniti M45 (Y34). Manual - part 332

PRECAUTIONS

EC-17

PRECAUTIONS

PFP:00001

Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”

ABS004SC

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 SRS and SB section of this Service Man-
ual.

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 per-
formed by an authorized NISSAN/INFINITI dealer.

●

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS 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.

On Board Diagnostic (OBD) System of Engine and A/T

ABS002CW

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 terminal 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-53, "HAR-

NESS CONNECTOR"

●

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

ABS002CX

●

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 con-
nector, turn ignition switch OFF and disconnect battery
ground 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.

SEF289H

EC-18

PRECAUTIONS

●

Do not disassemble ECM.

●

If a battery terminal 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 dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.

●

When connecting ECM harness connector, fasten it
securely with a lever as far as it will go as shown in the fig-
ure.

●

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 sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.

●

Keep engine control system parts and harness dry.

SEF707Y

PBIB1162E

PBIB1163E

PBIB0090E

PRECAUTIONS

EC-19

●

Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to

EC-98, "ECM Terminals and Reference Value"

●

Handle mass air flow sensor carefully to avoid damage.

●

Do not disassemble mass air flow sensor.

●

Do not clean mass air flow sensor with any type of deter-
gent.

●

Do not disassemble electric throttle control actuator.

●

Even a slight leak in the air intake system can cause seri-
ous incidents.

●

Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).

●

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

●

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.

●

Do not 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.

MEF040D

SEF217U

SEF348N

EC-20

PRECAUTIONS

●

B1 indicates the bank 1 and B2 indicates the bank 2 as
shown in the figure.

●

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 unneces-
sarily.

●

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 elec-
tronic control systems depending on installation location.

–

Keep the antenna as far as possible from the electronic
control units.

–

Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.

–

Adjust the antenna and feeder line so that the standing-
wave radio can be kept smaller.

–

Be sure to ground the radio to vehicle body.

Wiring Diagrams and Trouble Diagnosis

ABS002CY

When you read Wiring diagrams, refer to the following:

●