2007 NISSAN 350Z battery

SERVICE INFORMATION FOR ELECTRICAL INCIDENT
GI-31
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Revision: 2006 November2007 350Z
VOLTAGE CHECK METHOD
To help in understanding the diagnosis of open circuits please refer to the previous schematic.
In any powered circuit, an open can be found by methodically checking the system for the presence of voltage.
This is done by switching the DMM to the voltage function.

Connect one probe of the DMM to a known good ground.

Begin probing at one end of the circuit and work your way to the other end.

With SW1 open, probe at SW1 to check for voltage.
voltage; open is further down the circuit than SW1.
no voltage; open is between fuse block and SW1 (point A).

Close SW1 and probe at relay.
voltage; open is further down the circuit than the relay.
no voltage; open is between SW1 and relay (point B).

Close the relay and probe at the solenoid.
voltage; open is further down the circuit than the solenoid.
no voltage; open is between relay and solenoid (point C).
Any powered circuit can be diagnosed using the approach in the previous example.
Testing for “Shorts” in the Circuit
To simplify the discussion of shorts in the system, please refer to the following schematic.
RESISTANCE CHECK METHOD

Disconnect the battery negative cable and remove the blown fuse.

Disconnect all loads (SW1 open, relay disconnected and solenoid disconnected) powered through the
fuse.

Connect one probe of the DMM to the load side of the fuse terminal. Connect the other probe to a known
good ground.

With SW1 open, check for continuity.
continuity; short is between fuse terminal and SW1 (point A).
no continuity; short is further down the circuit than SW1.

Close SW1 and disconnect the relay. Put probes at the load side of fuse terminal and a known good
ground. Then, check for continuity.
continuity; short is between SW1 and the relay (point B).
no continuity; short is further down the circuit than the relay.

Close SW1 and jump the relay contacts with jumper wire. Put probes at the load side of fuse terminal and
a known good ground. Then, check for continuity.
continuity; short is between relay and solenoid (point C).
no continuity; check solenoid, retrace steps.
VOLTAGE CHECK METHOD

Remove the blown fuse and disconnect all loads (i.e. SW1 open, relay disconnected and solenoid discon-
nected) powered through the fuse.

Turn the ignition key to the ON or START position. Verify battery voltage at the battery + side of the fuse
terminal (one lead on the battery + terminal side of the fuse block and one lead on a known good ground).

With SW1 open and the DMM leads across both fuse terminals, check for voltage.
voltage; short is between fuse block and SW1 (point A).
SGI847-A

SERVICE INFORMATION FOR ELECTRICAL INCIDENT
GI-33
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Revision: 2006 November2007 350Z
If repairs are needed always use wire that is of the same or larger gauge.
MEASURING VOLTAGE DROP — ACCUMULATED METHOD

Connect the DMM across the connector or part of the circuit you want to check. The positive lead of the
DMM should be closer to power and the negative lead closer to ground.

Operate the circuit.

The DMM will indicate how many volts are being used to “push” current through that part of the circuit.
Note in the illustration that there is an excessive 4.1 volt drop between the battery and the bulb.
MEASURING VOLTAGE DROP — STEP-BY-STEP
The step-by-step method is most useful for isolating excessive drops in low voltage systems (such as those in
“Computer Controlled Systems”).
Circuits in the “Computer Controlled System” operate on very low amperage.
The (Computer Controlled) system operations can be adversely affected by any variation in resistance in the
system. Such resistance variation may be caused by poor connection, improper installation, improper wire
gauge or corrosion.
The step by step voltage drop test can identify a component or wire with too much resistance.
SGI974
SAIA0258E

GI-34
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
Revision: 2006 November2007 350Z
Control Unit Circuit Test
System Description:When the switch is ON, the control unit lights up the lamp.
INPUT-OUTPUT VOLTAGE CHART
The voltage value is based on the body ground.
*:If high resistance exists in the switch side circuit (caused by a single strand), terminal 1 does not detect battery voltage. Control unit
does not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not supply power to light up the
lamp.
INPUT-OUTPUT VOLTAGE CHART
The voltage value is based on the body ground.
*:If high resistance exists in the switch side circuit (caused by a single strand), terminal 2 does not detect approx. 0V. Control unit does
not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not control ground to light up the lamp.
MGI034A
Pin
No.Item ConditionVoltage
value [V]In case of high resistance such as single strand [V] *
1 SwitchSwitch ON Battery voltage Lower than battery voltage Approx. 8 (Example)
Switch OFF Approx. 0 Approx. 0
2LampSwitch ON Battery voltage Approx. 0 (Inoperative lamp)
Switch OFF Approx. 0 Approx. 0
MGI035A
Pin
No.Item ConditionVo l ta g e
value [V]In case of high resistance such as single strand [V] *
1LampSwitch ON Approx. 0 Battery voltage (Inoperative lamp)
Switch OFF Battery voltage Battery voltage
2 SwitchSwitch ON Approx. 0 Higher than 0 Approx. 4 (Example)
Switch OFF Approx. 5 Approx. 5

SERVICE INFORMATION FOR ELECTRICAL INCIDENT
GI-35
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Revision: 2006 November2007 350Z
Control Units and Electrical PartsNAS0009Q
PRECAUTIONS

Never reverse polarity of battery terminals.

Install only parts specified for a vehicle.

Before replacing the control unit, check the input and output and functions of the component parts.

Do not apply excessive force when disconnecting a connector.

Do not apply excessive shock to the control unit by dropping or
hitting it.

Be careful to prevent condensation in the control unit due to
rapid temperature changes and do not let water or rain get on it.
If water is found in the control unit, dry it fully and then install it in
the vehicle.

Be careful not to let oil to get on the control unit connector.

Avoid cleaning the control unit with volatile oil.

Do not disassemble the control unit, and do not remove the
upper and lower covers.

When using a DMM, be careful not to let test probes get close to
each other to prevent the power transistor in the control unit
from damaging battery voltage because of short circuiting.

When checking input and output signals of the control unit, use
the specified check adapter.
SAIA0255E
SEF348N