6-1-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table A-4 Malfunction Indicator Lamp
Check – MIL Does Not Flash or Just
Remains ON Even with Grounding
Diagnosis Switch Terminal (Vehicle with
Monitor Connector) ................................... 6-1-45
Table A-5 ECM (PCM) Power and Ground
Circuit Check – MIL Doesn’t Light at
Ignition Switch ON and Engine Doesn’t
Start Though It Is Cranked Up .................. 6-1-46
DTC P0100 (DTC No.33, 34) Mass Air
Flow Circuit Malfunction ............................ 6-1-48
DTC P0110 (DTC No.23, 25) Intake Air
Temp. (IAT) Circuit Malfunction ................ 6-1-50
DTC P0115 (DTC No.14, 15) Engine
Coolant Temp. Circuit Malfunction ............ 6-1-52
DTC P0120 (DTC No.21, 22) Throttle
Position Circuit Malfunction....................... 6-1-54
DTC P0121 Throttle Position Circuit
Range/Performance Problem ................... 6-1-56
DTC P0130 (DTC No.13) HO2S-1 (Bank 1)
Circuit Malfunction or No Activity
Detected.................................................... 6-1-58
DTC P0133 HO2S-1 (Bank 1) Circuit Slow
Response .................................................. 6-1-60
DTC P0135 HO2S-1 (Bank 1) Heater
Circuit Malfunction .................................... 6-1-61
DTC P0136 HO2S-2 (Bank 1) Circuit
Malfunction................................................ 6-1-63
DTC P0141 HO2S-2 (Bank 1) Heater
Circuit Malfunction .................................... 6-1-65
DTC P0150 (DTC No.26) HO2S-1 (Bank 2)
Circuit Malfunction or No Activity
Detected.................................................... 6-1-67
DTC P0153 HO2S-1 (Bank 2) Circuit Slow
Response .................................................. 6-1-69
DTC P0155 HO2S-1 (Bank 2) Heater
Circuit Malfunction .................................... 6-1-70
DTC P0156 HO2S-2 (Bank 2) Circuit
Malfunction................................................ 6-1-72
DTC P0161 HO2S-2 (Bank 2) Heater
Circuit Malfunction .................................... 6-1-74
DTC P0171/P0172 Fuel System Too
Lean/Rich (Bank 1) ................................... 6-1-76
DTC P0174/P0175 Fuel System Too
Lean/Rich (Bank 2) ................................... 6-1-78
DTC P0300/P0301/P0302/P0303/P0304/
P0305/P0306 Random Misfire/Cylinder 1
Misfire/Cylinder 2 Misfire/Cylinder 3 Misfire/
Cylinder 4 Misfire Detected/Cylinder 5
Misfire Detected/Cylinder 6 Misfire
Detected.................................................... 6-1-80
DTC P0325 (DTC No.43) Knock Sensor Circuit Malfunction ..................................... 6-1-82
DTC P0335 Crankshaft Position Sensor
Circuit Malfunction ..................................... 6-1-84
DTC P0340 (DTC No.42) Camshaft
Position Sensor Circuit Malfunction ........... 6-1-86
DTC P0400 Exhaust Gas Recirculation
Flow Malfunction ........................................ 6-1-89
DTC P0403 (DTC No.51) Exhaust Gas
Recirculation Circuit Malfunction ............... 6-1-92
DTC P0420 Catalyst System Efficiency
Below Threshold (Bank 1) ......................... 6-1-94
DTC P0430 Catalyst System Efficiency
Below Threshold (Bank 2) ......................... 6-1-96
DTC P0443 Evap Control System Purge
Control Valve Circuit Malfunction............... 6-1-98
Evap canister purge system
inspection ............................................. 6-1-100
Vacuum passage inspection ................ 6-1-100
Vacuum hose inspection ...................... 6-1-101
Evap canister purge valve and its
circuit inspection .................................. 6-1-101
Evap canister purge valve inspection .. 6-1-101
DTC P0460 Fuel Level Sensor Circuit
High Input ................................................ 6-1-103
DTC P0500 (DTC No.24) Vehicle Speed
Sensor Malfunction .................................. 6-1-105
DTC P0505 Idle Air Control System
Malfunction .............................................. 6-1-108
DTC P0601 (DTC No.71) Internal Control
Module Memory Check Sum Error .......... 6-1-110
DTC P1408 Manifold Absolute Pressure
Sensor Circuit Malfunction ....................... 6-1-111
DTC P1450/P1451 Barometric Pressure
Sensor Circuit Malfunction/Performance
Problem ................................................... 6-1-113
DTC P1500 Engine Starter Signal Circuit
Malfunction .............................................. 6-1-114
DTC P1510 Ecm Back-Up Power Supply
Malfunction .............................................. 6-1-115
Table B-1 Fuel Pump Circuit Inspection .. 6-1-116
Table B-2 Fuel Injectors and Circuit
Inspection ................................................ 6-1-117
Table B-3 Fuel Pressure Inspection ........ 6-1-119
Table B-4 Idle Air Control System
Inspection ................................................ 6-1-121
Table B-5 A/C Signal Circuits Inspection
(If Equipped) ............................................ 6-1-123
Table B-6 A/C Condenser Fan Motor
Relay Control System Inspection
(If Equipped) ............................................ 6-1-124
Special Tool ............................................... 6-1-125
6-1-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
P0174 Fuel system too lean (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is larger
than specification for specified time or
longer. (Fuel trim toward rich side is
large.)2 driving
cyclesNot
applicable
P0175 Fuel system too rich (Bank 2)Short term fuel trim or total fuel trim
(short and long terms added) is
smaller than specification for specified
time or longer. (Fuel trim toward lean
side is large.)2 driving
cyclesNot
applicable
P0300
P0301
P0302
P0303
P0304
P0305
P0306Random misfire detected
Cylinder 1 misfire detected
Cylinder 2 misfire detected
Cylinder 3 misfire detected
Cylinder 4 misfire detected
Cylinder 5 misfire detected
Cylinder 6 misfire detectedMisfire of such level as to cause dam-
age to three way catalystMIL flashing
during mis-
fire detec-
tionNot
applicable
Misfire of such level as to deteriorate
emission but not to cause damage to
three way catalyst2 driving
cyclesNot
applicable
P0325
(No.43)Knock sensor circuit malfunc-
tionSensor output too low
1 driving
cycle1 driving
cycle
Sensor output too high
P0335Crankshaft position sensor cir-
cuit malfunctionNo signal during engine running and
CMP sensor signal inputting1 driving
cycleNot
applicable
P0340
(No.42)Camshaft position sensor cir-
cuit malfunctionNo signal for 3 sec. during engine
cranking, REF signal pattern incor-
rect or POS signal voltage too high or
too low1 driving
cycleNot
applicable
P0400Exhaust gas recirculation flow
malfunction detectedExcessive or insufficient EGR flow.2 driving
cyclesNot
applicable
P0403
(No.51)EGR valve circuit malfunctionEGR valve electrical circuit open or
shot to ground1 driving
cycle1 driving
cycle
P0420Catalyst system efficiency
below threshold (Bank 1)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0430Catalyst system efficiency
below threshold (Bank 2)Output waveforms of HO2S-1 and
HO2S-2 are similar.
(Time from output voltage change of
HO2S-1 to that of HO2S-2 is shorter
than specification.)2 driving
cyclesNot
applicable
P0443Purge control valve circuit
malfunctionPurge control valve circuit is open or
shorted to ground.2 driving
cyclesNot
applicable
P0500
(No.24)Vehicle speed sensor mal-
functionNo signal while running in “D” range
or during fuel cut at decelerating.2 driving
cycles1 driving
cycle DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without
monitor
connector)MIL
(vehicle
with
monitor
connector)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-31
Engine Diagnosis Table
Perform troubleshooting referring to following table when ECM (PCM) has detected no DTC and no abnormality
has been found in visual inspection and engine basic inspection previously.
Condition Possible Cause Correction
Hard starting
(Engine cranks OK)Faulty idle air control system “DIAG. FLOW TABLE B-4” in this
section.
Faulty ECT sensor or MAF sensor ECT sensor or MAF sensor in Sec-
tion 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Compression check in Section
6A2.
Faulty hydraulic valve lash adjuster Valve lash adjuster in Section 6A2.
Compression leak from valve seat Valves inspection in Section 6A2.
Sticky valve stem Valves inspection in Section 6A2.
Weak or damaged valve springs Valves spring inspection in Section
6A2.
Compression leak at cylinder head gasket Cylinder head inspection in Section
6A2.
Sticking or damaged piston ring Piston ring inspection in Section
6A2.
Worn piston, ring or cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Malfunctioning PCV valve PCV system inspection in Section
6E2.
Engine has no power
Engine overheating Refer to “OVERHEATING” in this
table.
Defective spark plug Spark plugs in Section 6F2.
Faulty ignition coil with ignitor Ignition coil in Section 6F2.
Fuel pressure out of specification
(dirty fuel filter, dirty or clogged fuel hose or
pipe, malfunctioning fuel pressure regulator,
malfunctioning fuel pump)“DIAG. FLOW TABLE B-3” in this
section.
Maladjusted TP sensor installation angle TP sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector in Section 6E2.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty ECM (PCM) Inspection of ECM (PCM) and its
circuit in this section.
Low compression Refer to the same item in “HARD
STARTING” of this table.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
6-1-40 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
C51-1-10A/T input speed sensor (–)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-11A/T input speed sensor (+)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-12 Camshaft position sensor 1Deflects between
0 – 1 V and 4 – 6 VIgnition switch ON, crankshaft
turned slowly
C51-1-13 Camshaft position sensor 2Deflects between
0 – 1 V and 4 – 6 VIgnition switch ON, crankshaft
turned slowly
C51-1-14 Vehicle speed sensorDeflects between
0 – 1 V and over 4VIgnition switch ON, Rear right tire
turned slowly with rear left tire
locked
C51-1-15 EVAP canister purge valve 10 – 14 V Ignition switch ON
C51-1-16 IAC valve (stepper motor coil 4) – –
C51-1-17 IAC valve (stepper motor coil 3) – –
C51-1-18Transmission range switch “D”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“D” range
0 – 1 VIgnition switch ON, selector lever :
Other than “D” range
C51-1-19Transmission range switch “N”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“N” range
0 – 1 VIgnition switch ON, selector lever :
Other than “N” range
C51-1-20Shield wire ground for A/T output
speed sensor (A/T vehicle)––
C51-1-21Shield wire ground for A/T input
speed sensor (A/T vehicle)––
C51-1-22A/T output speed sensor (–)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-23A/T output speed sensor (+)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-24 Engine start signal10 – 14 V While engine cranking
0 – 1 V Other than above
C51-1-25 Power steering pressure switch10 – 14 V Ignition switch ON
0 – 1 VWith engine running at idle speed,
turning steering wheel to the right or
left as far as it stops
C51-1-26 4WD low switch0 – 1 VIgnition switch ON, Transfer lever :
4WD low range
10 – 14 VIgnition switch ON, Transfer lever :
4H or 2H range
C51-1-27Transmission range switch “L”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“L” range
0 – 1 VIgnition switch ON, selector lever :
Other than “L” range
C51-1-28Transmission range switch “2”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“2” range
0 – 1 VIgnition switch ON, selector lever :
Other than “2” range TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-41
C51-2-1 Fuel injector No.2
10 – 14 V Ignition switch ON
C51-2-2 Fuel injector No.1
C51-2-3 – – –
C51-2-4Heater of HO2S-1 (bank 1)
(if equipped)10 – 14 V Ignition switch ON
0 – 2 VAt specified idle speed after engine
warmed up
C51-2-5Heater of HO2S-1 (bank 2)
(if equipped)10 – 14 V Ignition switch ON
0 – 2 VAt specified idle speed after engine
warmed up
C51-2-6 – – –
C51-2-7 Ground – –
C51-2-8 Fuel injector No.4
10 – 14 V Ignition switch ON
C51-2-9 Fuel injector No.3
C51-2-10 – – –
C51-2-11 – – –
C51-2-12EGR valve (stepper motor coil 4)
(if equipped)0 – 1 V
Ignition switch ON C51-2-13EGR valve (stepper motor coil 3)
(if equipped)10 – 14 V
C51-2-14EGR valve (stepper motor coil 2)
(if equipped)10 – 14 V
C51-2-15EGR valve (stepper motor coil 1)
(if equipped)0 – 1 V
C51-2-16Heater of HO2S-2 (bank 1)
(if equipped)10 – 14 V Ignition switch ON
0 – 1 VAt specified idle speed after engine
warmed up
C51-2-17Heater of HO2S-2 (bank 2)
(if equipped)10 – 14 V Ignition switch ON
0 – 1 VAt specified idle speed after engine
warmed up
C51-2-18 – – –
C51-2-19Crankshaft position sensor (+)
(if equipped)––
C51-2-20Crankshaft position sensor (–)
(if equipped)––
C51-2-21 Fuel injector No.6
10 – 14 V Ignition switch ON
C51-2-22 Fuel injector No.5
C51-2-23 Ignition coil assembly for No.6 – –
C51-2-24 Ignition coil assembly for No.5 – –
C51-2-25 Ignition coil assembly for No.4 – –
C51-2-26 Ignition coil assembly for No.3 – –
C51-2-27 Ignition coil assembly for No.2 – –
C51-2-28 Ignition coil assembly for No.1 – –
C51-2-29 – – –
C51-2-30Ground for CKP sensor shield wire
(if equipped)–– TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION
6-1-80 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 Random Misfire/Cylinder
1 Misfire/Cylinder 2 Misfire/Cylinder 3 Misfire/Cylinder 4 Misfire Detected/Cyl-
inder 5 Misfire Detected/Cylinder 6 Misfire Detected
SYSTEM DESCRIPTION
ECM (PCM) measures the angle speed of the crankshaft based on the pulse signal from the CKP sensor and
CMP sensor for each cylinder. If it detects a large change in the angle speed of the crankshaft, it concludes
occurrence of a misfire. When the number of misfire is counted by the ECM (PCM) beyond the DTC detecting
condition, it determines the cylinder where the misfire occurred and outputs it as DTC.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and start
engine.
3) Increase vehicle speed to speed recorded as freeze frame data (V) ± 5 km/h when detecting misfire.
4) Keep driving above vehicle speed for 5 min.
5) Stop vehicle and check DTC (or pending DTC) by using scan tool.DTC DETECTING CONDITION TROUBLE AREA
DTC P0300 :
• Misfire which causes catalyst to overheat during 200 engine
revolutions is detected at 2 or more cylinders. (MIL flashes as
long as this misfire occurs continuously.)
• Misfire which affects exhaust emission adversely during 1000
engine revolutions is detected at 2 or more cylinders (2 driving
cycle detection logic)• Ignition system
• Fuel injector and its circuit
• Fuel line pressure
• Engine compression
• Abnormal air drawn in
• EGR system
• Fuel level sensor
• Valve lash adjuster
• Valve timing DTC P0301, P0302, P0303, P0304, P0305, P0306 :
• Misfire which causes catalyst to overheat during 200 engine
revolutions is detected at 1 cylinder. (MIL flashes as long as
this misfire occurs continuously.)
• Misfire which affects exhaust emission adversely during 1000
engine revolutions is detected at 1 cylinder
(2 driving cycle detection logic)
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. : – 8 – 70°C (18 – 158°F)
Engine coolant temp. : – 8°C (18°F) or higher
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-81
TROUBLESHOOTING
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE” in this
section.
2 Ignition system inspection :
1) Check spark plug and ignition spark of cylin-
der where misfire occurs, referring to “IGNI-
TION SYSTEM” section.
Is it in good condition?Go to Step 3. Faulty ignition coil, wire
harness, or other system
parts.
3 Fuel injector circuit inspection :
1) Using sound scope, check each injector
operating sound at engine cranking or
idling.
Do all injectors make operating sound?Go to Step 4. Check coupler connec-
tion and wire harness of
injector not making oper-
ating sound and injector
itself.
If OK, substitute a known-
good ECM (PCM) and
recheck.
4 Fuel pressure inspection :
1) Check fuel pressure referring to “TABLE B-
3” in this section.
Is check result satisfactory?Go to Step 5. Repair or replace.
5 Fuel injector inspection :
1) Check fuel injector(s) referring to Section
6E2.
Is check result satisfactory?Go to Step 6. Replace.
6 Ignition timing inspection :
1) Check ignition timing referring to Section
6F2.
Is check result satisfactory?Go to Step 7. Adjust or check system
related parts.
7 EGR system inspection :
1) Check EGR system referring to Section
6E2.
Is check result satisfactory?Go to Step 8. Repair or replace.
8 Fuel level sensor inspection :
1) Check fuel level sensor referring to Section
6E2.
Is check result satisfactory?Go to Step 9. Repair or replace.
9 Check engine mechanical parts or system
which can cause engine rough idle or poor per-
formance.
• Engine compression (See Section 6A2).
• Valve lash or lash adjuster (See Section
6A2).
• Valve timing (Timing belt or chain installa-
tion. See Section 6A2).
Are they in good condition?Check wire harness and
connection of ECM (PCM)
ground, ignition system
and fuel injector for inter-
mittent open and short.Repair or replace.
6-1-84 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0335 Crankshaft Position Sensor Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and run
engine at idle speed for 10 sec.
3) Check DTC by using scan tool.
1. CKP sensor
2. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
CKP sensor signal is not input while 100 pulses of
CMP sensor signal are input after engine start.CKP sensor circuit
CKP sensor
ECM (PCM)
NOTE:
Check to make sure that following condition is satisfied when using this “DTC CONFIRMATION PRO-
CEDURE”.
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : – 8 – 110°C (18 – 230°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)