Downloaded from www.Manualslib.com manuals search engine 1A-28 Engine General Information and Diagnosis:
Trouble area
• Scan tool
• Connector related to CAN line (included in DLC)
• CAN line
• Power or ground circuit of DLC
• Control module communicated by CAN
–ECM
–TCM
– ABS control module
–BCM
– Combination meter
– Keyless start control module
– 4WD control module
• Power or ground circuit of control module communicated by CAN
[A]: Non-Taiwan model[K]: Combination meter connector (viewed from terminal side)
[B]: Taiwan model1. ECM
[C]: DLC connector (viewed from terminal side) 2. ABS control module
[D]: ECM connector (viewed from harness side) 3. BCM
[E]: 4WD control module connector (viewed from harness side) 4. 4WD control module
[F]: TCM connector (viewed from harness side) 5. Combination meter
[G]: Keyless start control module connector (viewed from harness side) 6. Keyless start control module
[H]: BCM connector (viewed from harness side) (Non-taiwan model) 7. TCM
[I]: BCM connector (viewed from harness side) (Taiwan model) 8. CAN junction connector
[J]: ABS control module connector (viewed from terminal side) 9. DLC
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-29
Troubleshooting
Step Action Yes No
1Scan tool check
1) Disconnect scan tool from DLC with ignition switch
turned OFF.
2) Check for proper connection to all terminals of scan tool
connector.
3) If OK, connect scan tool to another vehicle of this type
with ignition switch turned OFF.
4) Check communication between scan tool and ECM by
DTC check in ECM.
Is it possible to check DTC in ECM?Go to Step 2. Scan tool faulty. Refer
to its operator’s manual.
2DLC power circuit check
1) Check for proper connection to all DLC (1) terminals with
ignition switch turned OFF.
2) If OK, measure voltage between +B terminal (2) of DLC
and vehicle body ground with ignition switch turned to
ON position.
Is voltage 10 – 14 V?Go to Step 3. Repair power circuit.
3DLC ground circuit check
1) Ignition switch turn to OFF position.
2) Check DLC (1) ground circuits as follows.
• Measure resistance between signal ground terminal
(2) of DLC and vehicle body ground.
• Measure resistance between body ground terminal (3)
of DLC and vehicle body ground.
Is resistance 1
Ω or less?Go to Step 4. Repair ground circuit(s).
4DTC Check
1) Turn ignition switch to OFF position.
2) Connect scan tool to DLC.
3) Check DTC in the following control modules that
communicate with scan tool by K-line.
•BCM
• Keyless start control module
• 4WD control module
Is there any DTC other than CAN-DTC?Go to applicable
troubleshooting of DTC
other than CAN-DTC.Go to Step 5.
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Downloaded from www.Manualslib.com manuals search engine 1A-30 Engine General Information and Diagnosis:
5CAN line check between DLC and BCM
1) Turn ignition switch to OFF position.
2) Disconnect BCM connector from BCM.
3) Check for proper connection to all terminals of BCM
connector.
4) If OK, check CAN lines between DLC and BCM
connector for open, short to power circuit, short to
ground circuit, short to other CAN line and high
resistance.
Are CAN lines between DLC and BCM connector in good
condition?Go to Step 6. Repair CAN line.
6Control module connector check
1) Turn ignition switch to OFF position.
2) Disconnect all the following control module connectors.
• Control modules communicated by CAN
–ECM
–TCM
– ABS control module
–BCM
– Combination meter
– Keyless start control module
– 4WD control module
3) Check for proper connection to each CAN line terminal
of all control module (communicated by CAN)
connectors.
4) If OK, connect connectors of all control module/sensor
communicated by CAN securely.
5) Check communication between scan tool and ECM/TCM
by DTC check in ECM/TCM.
Is it possible to check DTC in ECM and TCM?Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.Go to Step 7.
7CAN line check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of all control module
communicated by CAN.
3) Check all the following CAN lines for open, short to
power circuit, short to ground circuit, short to other CAN
line and high resistance.
• Between BCM connector and ABS control module
connector
• Between ABS control module connector and ECM
connector
• Between ECM connector and TCM connector
• Between BCM connector and keyless start control
module connector
• Between combination meter connector and 4WD
control module connector
• Between BCM connector and combination meter
connector
Are all CAN lines in good condition?Go to Step 8. Repair CAN line. Step Action Yes No
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-31
8Communication check between scan tool and ECM
1) Turn ignition switch to OFF position.
2) Connect ECM, BCM, ABS control module and
combination meter connectors.
3) Check communication between scan tool and ECM by
DTC check in ECM.
Is it possible to check DTC in ECM?A/T model: Go to Step
9.
M/T model: Substitute a
known-good ECM and
recheck.Go to Step 4 through
Step 11 of
“Troubleshooting for
CAN-DTC”.
9Communication check between scan tool and TCM
1) Turn ignition switch to OFF position.
2) Connect TCM connectors.
3) Check communication between scan tool and TCM by
DTC check in TCM.
Is it possible to check DTC in TCM?Identify malfunction
control module by
performing Step 13
through Step 14 of
“Troubleshooting for
CAN-DTC”.Go to Step 10.
10Internal circuit check in ECM
1) Turn ignition switch to OFF position and then disconnect
negative (–) cable at battery.
2) Disconnect TCM connectors.
3) Measure resistance between the followings
• Between CAN High terminal on DLC and “C06-17”
terminal on TCM connector
• Between CAN Low terminal on DLC and “C06-7”
terminal on TCM connector
Is each resistance 0 – 1
Ω?Substitute a known-
good TCM and recheck.Substitute a known-
good ECM and recheck. Step Action Yes No
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-43
THROTTLE MOTOR RELAY (ON/OFF)
ON: Throttle actuator (motor) control activated by ECM.
OF: Throttle actuator (motor) control stopped by ECM.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from front wheel
speed sensor (RH, LH) (for M/T model) or output shaft
speed sensor (VSS) (for A/T model).INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH,
msec.)
This parameter indicates time of the injector drive (valve
opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder for multiport fuel injection).
Visual InspectionS6RW0D1104008
Visually check the following parts and systems.
Engine Basic InspectionS6RW0D1104009
This check is very important for troubleshooting when ECM has detected no DTC and no abnormality has been found
in “Visual Inspection”.
Follow the flow carefully.Inspection item Reference section
• Engine oil – level, leakage “Engine Oil and Filter Change in Section 0B”
• Engine coolant – level, leakage “Coolant Level Check in Section 1F”
• Fuel – level, leakage“Fuel Lines and Connections Inspection in
Section 0B”
• Air cleaner element – dirt, clogging “Air Cleaner Filter Inspection in Section 0B”
• Battery – fluid level, corrosion of terminal“Battery Dismounting and Remounting in
Section 1J”
• Water pump belt – tension damage“Accessory Drive Belt Inspection in Section
0B”
• Throttle valve – operating sound“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
• Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend“Vacuum Hose Inspection in Section 1B”
• Connectors of electric wire harness – disconnection, friction
• Fuses – burning
• Parts – installation, bolt – looseness
• Parts – deformation
• Other parts that can be checked visually
Also check the following items at engine start, if possible
• Malfunction indicator lamp – Operation “Malfunction Indicator Lamp (MIL) Check”
• Charge warning lamp – Operation “Generator Symptom Diagnosis in Section 1J”
• Engine oil pressure warning lamp – Operation “Oil Pressure Switch Inspection in Section 9C”
• Engine coolant temp. meter – Operation“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C”
• Fuel level meter – Operation “Fuel Level Sensor Inspection in Section 9C”
• Tachometer – Operation
• Abnormal air being inhaled from air intake system
• Exhaust system – leakage of exhaust gas, noise
• Other parts that can be checked visually
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Check battery voltage
Is it 11 V or more?Go to Step 3. Charge or replace
battery.
3Is vehicle equipped with keyless start control system?Go to Step 4. Go to Step 5.
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-53
Troubleshooting
NOTE
• Before performed trouble shooting, be sure to read the “Precautions of ECM Circuit Inspection”.
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors referring to “Inspection of ECM and Its Circuits”.
Step Action Yes No
1MIL power supply check
1) Turn ignition switch to ON position.
Do other warning lights come ON?Go to Step 2. Go to Step 3.
2DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch and check DTC in ECM.
Is there DTC(s) U0073 and/or U0121?Go to applicable DTC
diag. flow.Go to Step 3.
3Combination meter power supply and ground circuit
check
1) Turn ignition switch OFF position.
2) Disconnect connector from combination meter.
3) Check for proper connection to power supply and
ground terminals of combination meter connector.
4) If connections are OK, check that combination meter
circuit is as follows.
• Circuit voltage between combination meter power
supply terminal and vehicle body ground is 10 –14 V.
• Wiring harness resistance of combination meter
ground terminal and vehicle body ground is less than
3 Ω.
Are they in good condition?Go to Step 4. Repair or replace.
4CAN communication line circuit check
1) Check CAN communication line circuit between control
modules for open, short, high resistance and
connections referring to Step 5 to 10 under
“Troubleshooting for Communication Error with Scan
Tool Using CAN”.
Is circuit in good condition?Substitute a known-
good combination meter
and recheck. If MIL still
remains OFF, substitute
a known-good ECM and
recheck.Repair or replace.
Downloaded from www.Manualslib.com manuals search engine 1A-56 Engine General Information and Diagnosis:
DTC Troubleshooting
NOTE
Before this troubleshooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Oil control valve electrical circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Check for proper connection at “C01-60” and “C01-59”
terminals of ECM connector.
3) If OK, measure resistance between “C01-60” and “C01-
59” terminals of ECM connector.
Is resistance below 10
Ω?Go to Step 3. Go to Step 8.
3Oil control valve electrical circuit check
Was resistance more than 6.5
Ω in Step 2?Go to Step 4. Go to Step 7.
4Oil control valve electrical circuit for power short check
1) Turn ON ignition switch.
2) Measure voltage between “C01-60” terminal of ECM
connector and engine ground.
Is voltage below 1 V?Go to Step 5. “RED”, “GRN/RED”,
“YEL” or “GRN/WHT”
wire is shorted to power
supply circuit.
5Oil control valve electrical circuit for ground short
check
1) Disconnect connector from oil control valve with ignition
switch turned OFF.
2) Measure resistance between “C01-60” terminal of ECM
connector and engine ground.
Is resistance infinity?Go to Step 6. “GRN/RED” wire is
shorted to ground
circuit.
6Oil control valve electrical circuit for ground short
check
1) Measure resistance between “C01-59” terminal of ECM
connector and engine ground.
Is resistance infinity?Go to Step 7. “GRN/WHT” wire is
shorted to ground
circuit.
7Oil control valve electrical circuit for short check
1) Disconnect connector from oil control valve with ignition
switch turned OFF.
2) Measure resistance between “C01-60” and “C01-59”
terminals of ECM connector.
Is resistance infinity?Go to Step 8. “GRN/RED” wire is
shorted to “GRN/WHT”
wire.
8Oil control valve electrical circuit check
1) Disconnect connector from oil control valve with ignition
switch turned OFF.
2) Measure resistance between “C01-60” terminal of ECM
connector and “GRN/RED” wire terminal of oil control
valve connector and between “C01-59” terminal of ECM
connector and “GRN/WHT” wire terminal of oil control
valve connector.
Is resistance below 1
Ω?Go to Step 9. “GRN/RED” wire or
“GRN/WHT” wire circuit
is open or high
resistance.
Downloaded from www.Manualslib.com manuals search engine 1A-60 Engine General Information and Diagnosis:
2HO2S-1 heater power circuit check
1) Disconnect connector from HO2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 at “BLK/WHT”
and “BLK/RED” wire terminals.
3) If wire and connection are OK, measure voltage
between “BLK/WHT” wire terminal and engine ground
with ignition switch turned ON.
Is voltage over 10 V?Go to Step 3. “BLK/WHT” wire is open
circuit or shorted to
ground circuit.
3HO2S-1 heater power circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “BLK/WHT” wire terminal
of HO2S-1 connector and “E01-29” terminal of ECM
connector.
Is resistance below 5
Ω?Go to Step 4. “BLK/WHT” wire is high
resistance circuit.
4HO2S-1 heater drive circuit check
1) Measure resistance between “C01-46” terminal of ECM
connector and vehicle body ground.
Is resistance infinity?Go to Step 5. “BLK/RED” wire is
shorted to ground
circuit.
5HO2S-1 heater drive circuit check
1) Turn ON ignition switch.
2) Measure voltage between “C01-46” terminal of ECM
connector and vehicle body ground.
Is voltage 0 V?Go to Step 6. “BLK/RED” wire is
shorted to power circuit.
6HO2S-1 heater drive circuit check
1) Connect connector to HO2S-1 with ignition switch turned
OFF.
2) Turn ON ignition switch.
3) Measure voltage between “C01-46” terminal of ECM
connector and vehicle body ground with connector
disconnected from ECM.
Is voltage over 10 V?Go to Step 7. “BLK/RED” wire is open
circuit.
7HO2S-1 heater check
1) Disconnect HO2S-1 connector with ignition switch
turned OFF.
2) Check HO2S-1 heater resistance referring to “Heated
Oxygen Sensor (HO2S-1 and HO2S-2) Heater On-
Vehicle Inspection (If Equipped) in Section 1C”.
Is resistance within specified value range?Go to Step 8. Replace HO2S-1.
8HO2S-1 heater power circuit check
1) Connect connector to HO2S-1 with ignition switch turned
OFF.
2) Measure resistance between “E01-29” and “C01-46”
terminals of ECM connector.
It resistance below 12
Ω?HO2S-1 heater circuit is
OK.
Substitute a known-
good ECM and recheck.“BLK/WHT”, “BLK/RED”
and / or “BLK” wire is
high resistance circuit. Step Action Yes No