SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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Revision: 2007 April2007 M35/M45
Cold or Hot Start Up
On some occasions an electrical incident may occur only when the car is started cold, or it may occur when
the car is restarted hot shortly after being turned off. In these cases you may have to keep the car overnight to
make a proper diagnosis.
CIRCUIT INSPECTION
Introduction
In general, testing electrical circuits is an easy task if it is approached in a logical and organized method.
Before beginning it is important to have all available information on the system to be tested. Also, get a thor-
ough understanding of system operation. Then you will be able to use the appropriate equipment and follow
the correct test procedure.
You may have to simulate vehicle vibrations while testing electrical components. Gently shake the wiring har-
ness or electrical component to do this.
NOTE:
Refer to “How to Check Terminal” to probe or check terminal.
Testing for “Opens” in the Circuit
Before you begin to diagnose and test the system, you should rough sketch a schematic of the system. This
will help you to logically walk through the diagnosis process. Drawing the sketch will also reinforce your work-
ing knowledge of the system.
CONTINUITY CHECK METHOD
The continuity check is used to find an open in the circuit. The digital multimeter (DMM) set on the resistance
function will indicate an open circuit as over limit (no beep tone or no ohms symbol). Make sure to always start
with the DMM at the highest resistance level.
To help in understanding the diagnosis of open circuits, please refer to the previous schematic.
Disconnect the battery negative cable.
Start at one end of the circuit and work your way to the other end. (At the fuse block in this example)
Connect one probe of the DMM to the fuse block terminal on the load side.
Connect the other probe to the fuse block (power) side of SW1. Little or no resistance will indicate that
portion of the circuit has good continuity. If there were an open in the circuit, the DMM would indicate an
over limit or infinite resistance condition. (point A)
Connect the probes between SW1 and the relay. Little or no resistance will indicate that portion of the cir-
cuit has good continuity. If there were an open in the circuit, the DMM would indicate an over limit or infi-
nite resistance condition. (point B)
Connect the probes between the relay and the solenoid. Little or no resistance will indicate that portion of
the circuit has good continuity. If there were an open in the circuit, the DMM would indicate an over limit or
infinite resistance condition. (point C)
Any circuit can be diagnosed using the approach in the previous example.
OPEN A circuit is open when there is no continuity through a section of the circuit.
SHORTThere are two types of shorts.
SHORT CIRCUITWhen a circuit contacts another circuit and causes the normal resistance to
change.
SHORT TO GROUND When a circuit contacts a ground source and grounds the circuit.
SGI846-A
GI-32
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
Revision: 2007 April2007 M35/M45
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: 2007 April2007 M35/M45
no voltage; short is further down the circuit than SW1.
With SW1 closed, relay and solenoid disconnected and the DMM leads across both fuse terminals, check
for voltage.
voltage; short is between SW1 and the relay (point B).
no voltage; short is further down the circuit than the relay.
With SW1 closed, relay contacts jumped with fused jumper wire check for voltage.
voltage; short is down the circuit of the relay or between the relay and the disconnected solenoid (point C).
no voltage; retrace steps and check power to fuse block.
Ground Inspection
Ground connections are very important to the proper operation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and other corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
Electronically controlled circuits are very sensitive to proper grounding. A loose or corroded ground can drasti-
cally affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit. Even
when the ground connection looks clean, there can be a thin film of rust on the surface.
When inspecting a ground connection follow these rules:
Remove the ground bolt or screw.
Inspect all mating surfaces for tarnish, dirt, rust, etc.
Clean as required to assure good contact.
Reinstall bolt or screw securely.
Inspect for “add-on” accessories which may be interfering with the ground circuit.
If several wires are crimped into one ground eyelet terminal, check for proper crimps. Make sure all of the
wires are clean, securely fastened and providing a good ground path. If multiple wires are cased in one
eyelet make sure no ground wires have excess wire insulation.
For detailed ground distribution information, refer to “Ground Distribution” in PG section.
Voltage Drop Tests
Voltage drop tests are often used to find components or circuits which have excessive resistance. A voltage
drop in a circuit is caused by a resistance when the circuit is in operation.
Check the wire in the illustration. When measuring resistance with DMM, contact by a single strand of wire will
give reading of 0 ohms. This would indicate a good circuit. When the circuit operates, this single strand of wire
is not able to carry the current. The single strand will have a high resistance to the current. This will be picked
up as a slight voltage drop.
Unwanted resistance can be caused by many situations as follows:
Undersized wiring (single strand example)
Corrosion on switch contacts
Loose wire connections or splices.
SGI853
GW-14
POWER WINDOW SYSTEM
Revision: 2007 April2007 M35/M45
POWER WINDOW SYSTEMPFP:25401
Component Parts and Harness Connector LocationNIS0021F
System DescriptionNIS0021G
Power is supplied at all time
through 50A fusible link (letter F , located in the fuse and fusible link box)
to BCM terminal 55, and
through BCM terminal 54
to power window main switch terminal 19
to power window sub-switch (front passenger side) terminal 10
to power window sub-switch (rear LH and RH) terminal 10.
through 10A fuse [No. 21, located in the fuse block (J/B)]
PIIB6097E
1. Fuse block (J/B) 2. Fusible link 3. BCM M1, M2, M3
4.Power window main switch D10,
D115. Power window sub-switch D46 6.Power window motor (front driver
side) D12
7. Power window motor (rear LH) D58 8. Front door switch driver side B11 9.Front door switch passenger side
B35
POWER WINDOW SYSTEM
GW-15
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to BCM terminal 42.
With ignition switch in ON or START position,
Power is supplied
through 15A fuse [No. 1, located in the fuse block (J/B)]
to BCM terminal 38, and
through BCM terminal 53
to power window main switch terminal 10
Ground supplied
to BCM terminal 52
through body grounds M16 and M70.
to power window main switch terminal 17
through body grounds M16 and M70.
to power window sub-switch (front passenger side) terminal 11
through body grounds M16 and M70.
to power window sub-switch (rear LH and RH) terminal 11
through body grounds B5, B40 and B131.
MANUAL OPERATION
Front Driver Side Door
WINDOW UP
When the front LH switch in the power window main switch is pressed in the up position,
Power is supplied
through power window main switch terminal 8
to power window motor (front driver side) terminal 2.
Ground is supplied
to power window motor (front driver side) terminal 1
through power window main switch terminal 11.
Then, the motor raises the window until the switch is released.
WINDOW DOWN
When the front LH switch in the power window main switch is pressed in the down position
Power is supplied
through power window main switch terminal 11
to power window motor (front driver side) terminal 1.
Ground is supplied
to power window motor (front driver side) terminal 2
through power window main switch terminal 8.
Then, the motor lowers the window until the switch is released.
GW-18
POWER WINDOW SYSTEM
Revision: 2007 April2007 M35/M45
ANTI-PINCH SYSTEM
Power window main switch and each power window sub-switch recognizes and controls the door glass condi-
tion by reading encoder signals 1 and 2.
If a door glass is subject to a certain resistance due to a foreign material obstruction during the following close
operation.
automatic close operation when ignition switch is in the “ON” position
automatic close operation during retained power operation
Key cylinder switch close operation during retained power operation
The power window switch reads encoder signal 1, It stops UP operation of the motor, and sends a signal for
down operation to lower the window by a certain amount (150mm, 5.91 in)
INITIALIZATION
Perform the initialization when the following operations are performed or when the auto up operation is not
performed. Refer to GW-63
(Front door), GW-68 (Rear door).
When the power supply to the power window main switch, power window sub-switch or each power win-
dow motor is cut off by the removal of battery terminal or the battery fuse is blown.
Disconnection and connection of power window main switch or each power window sub-switch harness
connector.
Removal and installation of regulator assembly.
Removal and installation of motor from regulator assembly.
Operation of regulator assembly as an independent unit.
Removal and installation of glass.
Removal and installation of door glass run.
CAUTION:
The following operations are not performed under the condition that the initialization is not per-
formed yet.
Auto up operation
Anti-pinch function
Key cylinder switch close operation
PIIB5952E
POWER WINDOW SYSTEM
GW-27
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Terminal and Reference Value for BCMNIS0021L
Te r m i -
nalWire
colorItemSignal
Input/
OutputConditionVoltage [V]
(Approx.)
12 PFront door switch
passenger side signalInputON (Open) 0
OFF (Close) Battery voltage
22 G Power window serial link Input/
OutputIGN SW ON or power window
timer operating.
38 W Ignition switch (ON or START) InputIgnition switch
(ON or START position)Battery voltage
39 L CAN - HInput/
Output——
40 P CAN - LInput/
Output——
42 P Power source (Fuse) Input — Battery voltage
52 B Ground — — 0
53 BR Rap signal OutputIGN SW ON Battery voltage
Within 45 second after ignition
switch is turned to OFFBattery voltage
When driver side or passenger
side door is opened daring
retained power operation0
54 O Power window power supply Output — Battery voltage
55 W Power source (Fusible link) Input — Battery voltage
62 VFront door switch
driver side signalInputON (Open) 0
OFF (Close) Battery voltage
PIIA2344J
GW-32
POWER WINDOW SYSTEM
Revision: 2007 April2007 M35/M45
Check BCM Power Supply and Ground CircuitNIS0021R
1. CHECK FUSE
Check 15A fuse [No. 1, located in fuse block (J/B)]
Check 10A fuse [No. 21, located in fuse block (J/B)]
Check 50A fusible link (letter F , located in the fuse and fusible link box).
NOTE:
Refer to GW-14, "
Component Parts and Harness Connector Location" .
OK or NG
OK >> GO TO 2.
NG >> If fuse is blown out, be sure to eliminate cause of malfunction before installing new fuse. Refer to
PG-3, "
POWER SUPPLY ROUTING CIRCUIT" .
2. CHECK POWER SUPPLY CIRCUIT
Check voltage between BCM connector and ground.
OK or NG
OK >> GO TO 3.
NG >> Check BCM power supply circuit for open or short.
3. CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect BCM connector.
3. Check continuity between BCM connector and ground.
OK or NG
OK >> Power supply and ground circuit are OK.
NG >> Check BCM ground circuit for open or short.
Te r m i n a l s
Condition of
ignition switchVoltage (V)
(Approx.) (+)
(–)
BCM connector Terminal
M1 38
GroundON
Battery voltage
M242
OFF
55
PIIB5934E
BCM connector Terminal
GroundContinuity
M2 52 Yes
PIIB5935E