Nissan PULSAR N13 Series / ASTRA LD Series. Manual - part 22
Fuel and Engine Management
89
The procedure for fabricating an LED test lamp is
fully described in the Electrical System section.
If a conventional test lamp with a filament type
bulb is to be used, ensure that the current draw of the
test lamp does not exceed 0.3 amp to avoid damage to
the electronic components.
To check the current draw connect an accurate
ammeter, such as the multimeter described previ-
ously, in series with the test lamp and a battery.
If the ammeter reads less than 0.3 amp the test
lamp is suitable.
Tachometer
(1) Disconnect the resistor from the tachometer
pick-up wiring connector which is located on the
ignition coil wiring harness, and connect the positive
lead of an accurate tachometer to the brown wire
terminal in the wiring connector.
(2) Connect the negative lead to a good earthing
point.
View showing the location of the tachometer pickup
wiring connector with the resistor installed.
Timing Light
(1) Connect the timing light to the engine fol-
lowing the instrument manufacturers instructions.
NOTE: Do not connect or disconnect the
timing light with the engine running as
voltage surges could damage the alternator
or control unit. Do not allow the high
tension leads to open circuit with the engine
running as damage to the engine manage-
ment system could result.
(2) Do not connect the timing light positive lead
to the alternator output terminal. Where possible,
connect the power leads of the timing light to an
external power source to prevent possible transient
voltages damaging the alternator or control unit.
4. SYSTEM DIAGNOSIS AND ADJUSTMENTS
NOTE: Due to the use of complex electronic
components in the engine management sys-
tem, the diagnosis and testing procedures
described in this section should not be
carried out by persons lacking an under-
standing of electronics and the precautions
associated with the servicing of electronic
components. It is recommended that should
a fault arise in the system, the vehicle be
referred to an authorized workshop.
The control unit can be damaged by
component faults not indicated by the self
diagnosis codes and the renewal of the
control unit without locating the cause of
the failure will result in the failure of the
replacement unit. It is for this reason that
the practice of substituting components to
isolate faults is not recommended.
Prior to performing any of the follow-
ing operations, refer to the Service Pre-
cautions and Procedures heading.
PRELIMINARY CHECKS
Prior to performing the Self Diagnosis Test Pro-
cedures, perform the following preliminary checks and
rectify any problems as necessary.
(1) Check for an adequate supply of fuel in the
fuel tank.
(2) Check the wiring connectors and earth points
of all engine management components for clean,
secure connections. To prevent damage to the control
unit, disconnect the negative battery terminal before
disconnecting any engine management wiring connec-
tors.
(3) Check the condition of the battery. Refer to
the Electrical System section for checking procedures.
Rectify any faults as necessary.
(4) Check the air cleaner element for restriction.
(5) Check for air leaks at the throttle body, inlet
manifold and all related hoses.
(6) Check the fuel pump pressure as described
later in this section.
(7) Ensure that the engine is in a satisfactory
mechanical condition and is in tune. Refer to the
Engine and Engine Tune-up sections as necessary.
SELF DIAGNOSIS
This function is very useful in locating system
faults particularly intermittent problems. However,
the self diagnosis mode does not provide comprehen-
sive testing of the engine management system, and
therefore should always be used in conjunction with
the other test procedures described later, in order to
accurately locate system faults.
To Interpret Self Diagnosis Codes
Once the self diagnosis mode is activated, various
fault codes will be displayed as a series of flashes by
the ECM warning lamp on the instrument cluster.