battery INFINITI FX35 2008 Service Manual
[x] Cancel search | Manufacturer: INFINITI, Model Year: 2008, Model line: FX35, Model: INFINITI FX35 2008Pages: 3924, PDF Size: 81.37 MB
Page 2722 of 3924
![INFINITI FX35 2008 Service Manual
EM-238
< SERVICE INFORMATION >[VK45DE]
ENGINE ASSEMBLY
1. Release fuel pressure. Refer to
EC-665, "Fuel Pressure Check".
2. Drain engine coolant from radiator. Refer to CO-37, "
Changing Engine Coo](/img/42/57017/w960_57017-2721.png "INFINITI FX35 2008 Service Manual
EM-238
< SERVICE INFORMATION >[VK45DE]
ENGINE ASSEMBLY
1. Release fuel pressure. Refer to
EC-665, \"Fuel Pressure Check\".
2. Drain engine coolant from radiator. Refer to CO-37, \"
Changing Engine Coo")
EM-238
< SERVICE INFORMATION >[VK45DE]
ENGINE ASSEMBLY
1. Release fuel pressure. Refer to
EC-665, "Fuel Pressure Check".
2. Drain engine coolant from radiator. Refer to CO-37, "
Changing Engine Coolant".
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
3. Disconnect both battery terminal. Refer to SC-4, "
How to Handle Battery".
4. Remove crankshaft position sensor (POS) from transmission. CAUTION:
Handle carefully to avoid dropping and shocks.
Do not disassemble.
Do not allow metal powder to adhere to magnetic part at sensor tip.
Do not place sensors in a location wh ere they are exposed to magnetism.
5. Remove the following parts: Hood assembly: Refer to BL-13, "
Fitting Adjustment".
Engine cover: Refer to EM-169
.
Front and rear engine undercover
Air duct (inlet), air duct and air cleaner case assembly: Refer to EM-173, "
Component".
Drive belts: Refer to EM-170, "
Component".
Radiator and radiator hoses (upper and lower): Refer to CO-40, "
Component".
Front road wheels and tires
Engine Room LH
1. Disconnect engine room harness from the engine side and set it aside for easier work.
2. Disconnect heater hoses, and install plugs to avoid leakage of engine coolant.
3. Disconnect ground cable from exhaust manifold cover to vehicle.
4. Disconnect vacuum hose between vehicle and engine and set it aside.
5. Discharge refrigerant from A/C circuit. Refer to ATC-120, "
HFC-134a (R-134a) Service Procedure".
6. Remove A/C piping from A/C compressor, and temporarily fasten it on vehicle with a rope. Refer to AT C -
121, "Component".
Engine Room RH
1. Disconnect fuel feed hose and EVAP hose. Refer to EM-190, "Component".
CAUTION:
Fit plugs onto disconnected hose to prevent fuel leak.
2. Disconnect engine room harness from the engine side and set it aside for easier work.
3. Disconnect ground cable from exhaust manifold cover to vehicle.
4. Disconnect vacuum hose between vehicle and engine and set it aside.
5. Disconnect reservoir tank of power steering oil pum p from engine, and move it aside for easier work.
CAUTION:
When temporarily securing, keep reservoir tank upright to avoid a fluid leak.
Vehicle Underbody
1. Remove front cross bar. Refer to FSU-5, "On-Vehicle Inspection and Service".
2. Disconnect power steering oil pump from engine. Move it from its location and secure with a rope for eas-
ier work. Refer to PS-29, "
Removal and Installation (VK45DE Models)".
3. Remove A/T fluid cooler tube. Refer to AT-241, "
Removal and Installation (2WD Models)".
4. Remove exhaust front tube and center muffler with power tool. Refer to EX-3, "
Checking Exhaust Sys-
tem".
5. Remove RH and LH transverse link mounting bolts and nuts. Refer to FSU-13, "
Removal and Installation".
6. Disconnect stabilizer connecting rod lower. Refer to FSU-5, "
On-Vehicle Inspection and Service".
7. Remove A/T control rod at control device assembly side. Then temporarily secure it on transmission, so
that it does not sag. Refer to AT-205, "
Control Device Removal and Installation".
8. Remove rear plate cover from oil pan. Then remove bolts fixing drive plate to torque converter. Refer to EM-183, "
Component" and AT-241, "Removal and Installation (2WD Models)".
9. Remove transmission joint bolts which pierce at oil pan lower rear side. Refer to AT-241, "
Removal and
Installation (2WD Models)".
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2835 of 3924
FUEL SYSTEMFL-3
< SERVICE INFORMATION >
C
DE
F
G H
I
J
K L
M A
FL
NP
O
FUEL SYSTEM
Checking Fuel LineINFOID:0000000001327104
Inspect fuel lines, fuel filler cap and fuel tank for improper attach-
ment, leaks, cracks, damage, loos
e connections, chafing or deterio-
ration.
If necessary, repair or replace damaged parts.
General PrecautionINFOID:0000000001327105
WARNING:
When replacing fuel line parts, be sure to observe the following.
• Put a “CAUTION: FLAMMABLE” sign in the workshop.
Be sure to work in a well ventila ted area and furnish workshop with a CO
2 fire extinguisher.
Do not smoke while servicing fuel system. Keep open flames and sparks away from the work area.
CAUTION:
Use gasoline required by the regulations for octane number. Refer to GI-5, "
Precaution for Fuel
(Unleaded Premium Gasoline Recommended)".
Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-proof containe r and put the lid on securely. Keep the container in
safe area.
- Release fuel pressure from th e fuel lines. Refer to EC-87, "
Fuel Pressure Check" (VQ35DE) or EC-
665, "Fuel Pressure Check" (VK45DE).
- Disconnect negative battery terminal.
Always replace O-ring and clamps with new ones.
Do not kink or twist tubes when they are being installed.
Do not tighten hose clamps excessi vely to avoid damaging hoses.
After connecting fuel tube qu ick connectors, make sure quick
connectors are secure.
Ensure that connector and resin tube do not contact any adja-
cent parts.
After installing tubes, make su re there is no fuel leakage at
connections in the following steps.
- Apply fuel pressure to fuel li nes with turning ignition switch
“ON” (with engine stopped). Th en check for fuel leaks at con-
nections.
- Start engine and rev it up and check for fuel leaks at connec- tions.
Use only a genuine NISSAN fuel filler cap as a replacement. If
an incorrect fuel filler cap is used, the “MIL” may come on.
For servicing “Evaporative Emi ssion System” parts, refer to
EC-40, "
Description" (VQ35DE) or EC-618, "Description"
(VK45DE).
For servicing“On Board Refueling Vapor Recovery (ORVR)”
parts, refer to EC-46, "
System Description" (VQ35DE) or EC-
624, "System Description" (VK45DE).
SMA803A
SBIA0504E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2838 of 3924
FL-6
< SERVICE INFORMATION >
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
Quick connector can be disconnected when the tabs are
completely depressed. Do not twist it more than neces-
sary.
Do not use any tools to disconnected quick connector.
Keep resin tube away from heat. Be especially careful when welding near the resin tube.
Prevent acid liquid such as battery electrolyte, etc. from getting on resin tube.
Do not bend or twist resin tube during installation and
disconnection.
Do not remove the remaining retainer on hard tube (or the equivalent) except when resin tube or retainer is
replaced.
When resin tube or hard tube (or the equivalent) is replaced, also replace retainer with new one.
To keep the connecting porti on clean and to avoid dam-
age and foreign materials, cover them completely with
plastic bags or something similar.
8. Remove main fuel level sensor unit, fuel filter and fuel pump assembly, and sub fuel level sensor unit as
follows:
CAUTION:
Do not bend float arm during removal.
Avoid impacts such as fallin g when handling components.
a. Removal of main fuel level sensor uni t, fuel filter and fuel pump assembly:
i. Remove retainer.
ii. Raise main fuel level sensor unit, fuel filter and fuel pump assembly, and using snap ring pliers, remove fuel hose connec-
tor.
CAUTION:
Be careful not to damage fu el hose connector by expanding
them excessively.
b. Removal of sub fuel level sensor unit:
i. Remove retainer.
ii. Raise and release sub fuel level sensor unit to remove.
INSTALLATION
Note to the following, and install in the reverse order of removal.
Main and Sub Fuel Level Sensor Unit
Retainer color: White
SBIA0504E
PBIC0163E
PBIC1578E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2863 of 3924
GI-1
GENERAL INFORMATION
C
DE
F
G H
I
J
K L
M B
GI
SECTION GI
N
O P
CONTENTS
GENERAL INFORMATION
SERVICE INFORMATION .. ..........................2
PRECAUTIONS .............................................. .....2
Description .......................................................... ......2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect .....................................
2
Precaution for Procedure without Cowl Top Cover ......3
General Precaution ...................................................3
Precaution for Three Way Catalyst ...........................4
Precaution for Fuel (Unleaded Premium Gasoline
Recommended) .........................................................
5
Precaution for Fuel (Unleaded Premium Gasoline
Required) ..................................................................
5
Precaution for Multiport Fuel Injection System or
Engine Control System .............................................
5
Precaution for Hoses .................................................5
Precaution for Engine Oils ........................................6
Precaution for the Environment .................................7
Precaution for Air Conditioning .................................7
HOW TO USE THIS MANUAL ............................8
Description .......................................................... ......8
Terms ........................................................................8
Units ..........................................................................8
Contents ....................................................................8
Component ................................................................8
How to Follow Trouble Diagnosis ..............................9
How to Read Wiring Diagram ..................................13
Abbreviations ..........................................................20
SERVICE INFORMATION FOR ELECTRICAL
INCIDENT ...........................................................
22
How to Check Terminal ....................................... ....22
How to Perform Efficient Diagnosis for an Electri-
cal Incident .......................................................... ....
25
Control Units and Electrical Parts ............................32
CONSULT-III/GST CHECKING SYSTEM .........34
Description ...............................................................34
CONSULT-III Function and System Application*1 ....34
CONSULT-III/GST Data Link Connector (DLC)
Circuit ......................................................................
35
Wiring Diagram - CONSULT-III/GST CHECKING
SYSTEM - ................................................................
36
LIFTING POINT .................................................37
Commercial Service Tool ........................................37
Garage Jack and Safety Stand ................................37
2-Pole Lift ................................................................38
Board-On Lift ...........................................................38
TOW TRUCK TOWING .....................................40
Tow Truck Towing ...................................................40
Vehicle Recovery (Freeing a Stuck Vehicle) ...........41
TIGHTENING TORQUE OF STANDARD
BOLTS ...............................................................
43
Tightening Torque Table .........................................43
RECOMMENDED CHEMICAL PRODUCTS
AND SEALANTS ...............................................
44
Recommended Chemical Product and Sealant .......44
IDENTIFICATION INFORMATION ....................45
Model Variation ........................................................45
Dimensions ..............................................................47
Wheels & Tires ........................................................47
TERMINOLOGY ................................................48
SAE J1930 Terminology List ...................................48
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2864 of 3924
GI-2
< SERVICE INFORMATION >
PRECAUTIONS
SERVICE INFORMATION
PRECAUTIONS
DescriptionINFOID:0000000001325649
Observe the following precautions to ensure safe and proper servicing. These precautions are not
described in each individual section.
Precaution for Supplemental Restraint S ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000001612904
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty 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 w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SUPPLEMENTAL RESTRAINT SYS-
TEM” and “SEAT BELTS” of this Service Manual.
WARNING:
• To avoid rendering the SRS inopera tive, 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 NISS AN/INFINITI dealer.
Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the “SUPPLEMEN TAL RESTRAINT SYSTEM”.
Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000001612934
NOTE:
This Procedure is applied only to models with In telligent Key system and NVIS/IVIS (NISSAN/INFINITI
VEHICLE IMMOBILIZER SYSTEM - NATS).
Remove and install all control units after disconnecting both battery cables with the ignition knob in the ″LOCK ″ position.
Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NVIS /IVIS, an electrically controlled steering lock
mechanism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of all control units using CONSULT-III.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2865 of 3924
PRECAUTIONSGI-3
< SERVICE INFORMATION >
C
DE
F
G H
I
J
K L
M B
GI
N
O P
Precaution for Procedur e without Cowl Top CoverINFOID:0000000001612933
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
General PrecautionINFOID:0000000001325654
Do not operate the engine for an extended period of time without
proper exhaust ventilation.
Keep the work area well ventilated and free of any flammable
materials. Special care should be taken when handling any flam-
mable or poisonous materials, such as gasoline, refrigerant gas,
etc. When working in a pit or ot her enclosed area, be sure to prop-
erly ventilate the area before working with hazardous materials.
Do not smoke while working on the vehicle.
Before jacking up the vehicle, apply wheel chocks or other tire
blocks to the wheels to prevent the vehicle from moving. After jack-
ing up the vehicle, support the vehicle weight with safety stands at
the points designated for proper lifting before working on the vehi-
cle.
These operations should be done on a level surface.
When removing a heavy component such as the engine or tran- saxle/transmission, be careful not to lose your balance and drop
them. Also, do not allow them to strike adjacent parts, especially
the brake tubes and master cylinder.
Before starting repairs which do not require battery power: Turn off ignition switch.
Disconnect the negative battery terminal.
If the battery terminals are disconnected, recorded memory of radio and each control unit is erased.
Battery posts, terminals and related accessories contain lead and
lead compounds. Wash hands after handling.
PIIB3706J
SGI285
SGI231
SEF289H
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2867 of 3924
PRECAUTIONSGI-5
< SERVICE INFORMATION >
C
DE
F
G H
I
J
K L
M B
GI
N
O P
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three
way catalyst.
Precaution for Fuel (Unlead ed Premium Gasoline Recommended)INFOID:0000000001325656
VQ35DE
INFINITI recommends the use of unleaded premium gasoli ne with an octane rating of at least 91 AKI (Anti-
Knock Index) number (Research octane number 96).
If unleaded premium gasoline is not available, you may use unleaded regular gasoline with an octane rating of
at least 87AKI number (Research octane number 91), but you may notice a decrease in performance.
CAUTION:
Do not use leaded gasoli ne. Using leaded gasoline will damage the three way catalyst. Do not use E-85
fuel (85% fuel ethanol, 15% unlead ed gasoline) unless the vehicle is specifically designed for E-85 fuel
(i.e. Flexible Fuel Vehicle - FFV models). Using a fu el other than that specified could adversely affect
the emission control devices and systems, and could also affect the warranty coverage validity.
Precaution for Fuel (Unleaded Premium Gasoline Required)INFOID:0000000001325657
VK45DE
Use unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-Knock Index) number (Research
octane number 96).
If unleaded premium gasoline is not available, unleaded r egular gasoline with an octane rating of at least 87
AKI number (Research octane number 91) can be us ed, but only under the following precautions:
have the fuel tank filled only partially with unl eaded regular gasoline, and fill up with unleaded premium gas-
oline as soon as possible.
avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the u se of unleaded premium gasoline is recommended.
CAUTION:
Do not use leaded gasoli ne. Using leaded gasoline will damage the three way catalyst. Do not use E-85
fuel (85% fuel ethanol, 15% unlead ed gasoline) unless the vehicle is specifically designed for E-85 fuel
(i.e. Flexible Fuel Vehicle - FFV models). Using a fu el other than that specified could adversely affect
the emission control devices and systems, and could also affect the warranty coverage validity.
Precaution for Multiport Fuel Inject ion System or Engine Control SystemINFOID:0000000001325658
Before connecting or disconnecti ng any harness connector for the
multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
Before disconnecting pressurized fuel line from fuel pump to injec- tors, be sure to release fuel pressure.
Be careful not to jar components such as ECM and mass air flow sensor.
Precaution for HosesINFOID:0000000001325659
HOSE REMOVAL AND INSTALLATION
SGI787
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2872 of 3924
GI-10
< SERVICE INFORMATION >
HOW TO USE THIS MANUAL
3.Refer to Component Parts and Harness Connector Location for the Systems described in each
section for identifi cation/location of componen ts and harness connectors.
4. Refer to the Circuit Diagra m for quick pinpoint check.
If you need to check circuit continuity between harness connectors in more detail, such as when a
sub-harness is used, refer to Wiring Diagram in each individual section and Harness Layout in PG
section for identificatio n of harness connectors.
5. When checking circuit continuity, ignition switch should be OFF.
6. Before checking voltage at co nnectors, check battery voltage.
7. After accomplishing the Diagnost ic Procedures and Electrical Components Inspection, make sure
that all harness connectors ar e reconnected as they were.
HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES
1.Work and diagnostic procedure
Start to diagnose a problem using procedures indicated in enclosed test groups.
2. Questions and required results
Questions and required results are indicated in bold type in test group.
The meaning of are as follows:
3. Symbol used in illustration
Symbols included in illustrations refer to measur ements or procedures. Before diagnosing a problem,
familiarize yourself with each symbol. Refer to "Connector Symbols" in GI Section and "KEY TO SYM-
BOLS SIGNIFYING MEASUREME NTS OR PROCEDURES" below.
4. Action items
Next action for each test group is indicated based on result of each question. Test group number is shown
in the left upper portion of each test group.
HARNESS WIRE COLOR AND CONNECTOR NUMBER INDICATION
There are two types of harness wire color and connector number indication.
TYPE 1: Harness Wire Color and Connec tor Number are Shown in Illustration
SAIA0256E
a. Battery voltage → 11 - 14V or approximately 12V
b. Voltage : Approximately 0V → Less than 1V
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2878 of 3924
GI-16
< SERVICE INFORMATION >
HOW TO USE THIS MANUAL
Optional Splice
DESCRIPTION
SGI942
Num-ber Item Description
1 Power condition This shows the condition when the system receives battery positive voltage (can be operated).
2Fusible link The double line shows that this is a fusible link.
The open circle shows current flow in, and the shaded circle shows current flow out.
3 Fusible link/fuse loca-
tion This shows the location of the fusible link or fuse in the fusible link or fuse box. For arrange-
ment, refer to PG section, POWER SUPPLY ROUTING.
4Fuse The single line shows that this is a fuse.
The open circle shows current flow in, and the shaded circle shows current flow out.
5 Current rating This shows the current rating of the fusible link or fuse.
6 Connectors This shows that connector E3 is female and connector M1 is male.
The G/R wire is located in the 1A terminal of both connectors.
Terminal number with an alphabet (1A, 5B, etc.) indicates that the connector is SMJ connector.
Refer to PG section, SMJ (SUPER MULTIPLE JUNCTION).
7 Optional splice The open circle shows that the splice is optional depending on vehicle application.
8 Splice The shaded circle shows that the splice is always on the vehicle.
9 Page crossing This arrow shows that the circuit continues to an adjacent page.
The A will match with the A on the preceding or next page.
10 Common connector The dotted lines between terminals show that these terminals are part of the same connector. 11 Option abbreviation This shows that the circuit is optional depending on vehicle application.
12 Relay This shows an internal representation of the relay. For details, refer to PG section, STAN-
DARDIZED RELAY.
13 Connectors This shows that the connector is connected to the body or a terminal with bolt or nut.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C
Page 2890 of 3924
GI-28
< SERVICE INFORMATION >
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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 test ing 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 circ uit. The digital multimeter (DMM) set on the resistance
function will indicate an open circuit as over limit (no beep tone or no ohms symbo\
l). Make sure to always start
with the DMM at the highest resistance level.
To help in understanding the diagnosis of open circui ts, 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 por-
tion 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 circuit
has good continuity. If there were an open in the circuit, t he DMM would indicate an over limit or infinite resis-
tance 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 ci rcuit, the DMM would indicate an over limit or infi-
nite resistance condition. (point C)
Any circuit can be diagnosed using the approach in the previous example.
VOLTAGE CHECK METHOD
To help in understanding the diagnosis of open circui ts please refer to the previous schematic.
In any powered circuit, an open can be found by methodica lly 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).
OPEN A circuit is open when there is no continuity through a section of the circuit.
SHORT There are two types of shorts.
SHORT CIRCUIT
When 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
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C