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
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-5
Fuel Pressure Relief Procedure
After making sure that engine is cold, relief fuel pressure as fol-
lows.
1) Place transmission gear shift lever in “Neutral” (shift selector
lever to “P” range for A/T vehicle), set parking brake, and
block drive wheels.
2) Remove fuel pump relay (1) from its connector.
3) Remove fuel filler cap to release fuel vapor pressure in fuel
tank and then reinstall it.
4) Start engine and run it till it stops for lack of fuel. Repeat
cranking engine 2 – 3 times of about 3 seconds each time to
dissipate fuel pressure in lines. Fuel connections are now
safe for servicing.
5) Upon completion of servicing, install fuel pump relay to relay
box.
Fuel Leakage Check Procedure
After performing any service on fuel system, check to make sure
that there are no fuel leakages as follows.
1) Turn ON ignition switch for 3 seconds (to operate fuel pump)
and then turn it OFF.
Repeat this (ON and OFF) 3 or 4 times and apply fuel pres-
sure to fuel line (till fuel pressure is felt by hand placed on
fuel return hose).
2) In this state, check to see that there are no fuel leakages
from any part of fuel system. CAUTION:
This work must not be done when engine is hot. If done
so, it may cause adverse effect to catalyst.
[A] : Left hand steering vehicle
[B] : Right hand steering vehicle
2. Fuse box
6-1-14 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
STEP 6. AND 7. RECHECKING AND RECORD OF DTC
Refer to “DTC Check” in this section for checking procedure.
STEP 8. ENGINE BASIC INSPECTION AND ENGINE DIAGNOSIS TABLE
Perform basic engine check according to the “ENGINE BASIC INSPECTION FLOW TABLE” first. When the end
of the flow table has been reached, check the parts of the system suspected as a possible cause referring to
“ENGINE DIAGNOSIS TABLE” and based on symptoms appearing on the vehicle (symptoms obtained through
steps of customer complaint analysis, trouble symptom confirmation and/or basic engine check) and repair or
replace faulty parts, if any.
Engine Basic Inspection Flow Table
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 Check battery voltage.
Is it 11 V or more?Go to Step 3. Charge or replace battery.
3 Is engine cranked? Go to Step 4. Go to “DIAGNOSIS” in
Section 6H.
4 Does engine start? Go to Step 5. Go to Step 7.
5 Check engine idle speed/IAC duty referring to
“IDLE SPEED/IAC DUTY INSPECTION” in
Section 6E2.
Is check result as specified?Go to Step 6. Go to “ENGINE DIAGNO-
SIS TABLE” in this sec-
tion.
6 Check ignition timing referring to “IGNITION
TIMING INSPECTION” in Section 6F2.
Is check result as specified?Go to “ENGINE DIAGNO-
SIS TABLE” in this sec-
tion.Adjust ignition timing.
7 Check fuel supply as follows :
1) Check to make sure that enough fuel is
filled in fuel tank.
2) Turn ON ignition switch for 3 seconds and
then OFF.
Repeat this a few times.
Is fuel return pressure (returning sounds) felt
from fuel return hose when ignition switch is
turned ON?Go to Step 9. Go to Step 8.
8 Check fuel pump for operating.
1) Was fuel pump operating sound heard from
fuel filler for about 3 seconds after ignition
switch ON and stop?Go to “DIAG. FLOW
TABLE B-3” in this sec-
tion.Go to “DIAG. FLOW
TABLE B-1” in this sec-
tion.
9 Check ignition spark referring to “IGNITION
SPARK TEST” in Section 6E2.
Is it in good condition?Go to Step 10. Go to “DIAGNOSIS” in
Section 6F2.
10 Check fuel injector referring to “Fuel INJECTOR
INSPECTION” in Section 6E2.
Is it in good condition?Go to “ENGINE DIAGNO-
SIS TABLE” in this sec-
tion.Go to “DIAG. FLOW
TABLE B-2” in this sec-
tion.
6-1-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Poor gasoline mileage
Faulty spark plug (improper gap, heavy depos-
its, and burned electrodes, etc.)Spark plugs in Section 6F2.
Fuel pressure out of specification “DIAG. FLOW TABLE B-3” in this
section.
Faulty TP sensor, ECT sensor or MAF sensor TP sensor, ECT sensor or MAF
sensor in Section 6E2.
Faulty EGR system “DTC P0400 DIAG. FLOW TABLE”
in this section.
Faulty injector Fuel injector 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.
Poor valve seating Valves inspection in Section 6A2.
Dragging brakes Diagnosis in Section 5.
Slipping clutch Diagnosis in Section 7C1.
Thermostat out of order Thermostat in Section 6B.
Improper tire pressure Diagnosis in Section 3.
Excessive engine oil
consumptionSticky piston ring Piston cleaning in Section 6A2.
Worn piston and cylinder Cylinders, pistons and piston rings
inspection in Section 6A2.
Worn piston ring groove and ring Pistons and piston rings inspection
in Section 6A2.
Improper location of piston ring gap Pistons installation in Section 6A2.
Worn or damaged valve stem seal Valves and cylinder head in Sec-
tion 6A2.
Worn valve stem Valves inspection in Section 6A2.
Low oil pressure
Improper oil viscosity Engine oil and oil filter change in
Section 0B.
Malfunctioning oil pressure switch Oil pressure switch inspection in
Section 8.
Clogged oil strainer Oil pan and oil pump strainer clean-
ing in Section 6A2.
Functional deterioration of oil pump Oil pump in Section 6A2.
Worn oil pump relief valve Oil pump in Section 6A2.
Excessive clearance in various sliding parts “INSPECTION” for each parts in
Section 6A2. Condition Possible Cause Correction
6-1-38 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
E61-22A/C condenser fan motor relay
(if equipped)10 – 14 VIgnition switch ON, A/C not oper-
ated and Engine coolant temp. :
less than 113°C, 235°F
E61-23 Fuel pump relay0 – 2.5 VFor 3 sec. after ignition switch ON
or while engine running
10 – 14 VAfter 3 sec. from ignition switch ON
with engine stopped
E61-24Ground for CO adjusting resistor
(if equipped)––
E61-25 – – –
E61-26 – – –
E61-27 – – –
E61-28 Fuel level sensor 0 – 6 VIgnition switch ON
Voltage depends on fuel level
E61-29Diag. switch terminal
(vehicle with monitor connector)10 – 14 V Ignition switch ON
E61-30 ABS control module 10 – 14 V Ignition switch ON
E61-31Power/Normal change switch
(A/T vehicle)0 – 1 VIgnition switch ON, P/N change
switch : POWER mode
10 – 14 VIgnition switch ON, P/N change
switch : NORMAL mode
E61-32 Lighting switch0 – 1 VIgnition switch ON, lighting switch
OFF
10 – 14 VIgnition switch ON, lighting switch
ON
E61-33 Overdrive cut switch (A/T vehicle)10 – 14 VIgnition switch ON, overdrive cut
switch released
0 – 1 VIgnition switch ON, overdrive cut
switch pressed
E61-34 Stop lamp switch0 – 1 VBrake pedal released (switch OFF),
Ignition switch ON
10 – 14 VBrake pedal depressed (switch ON),
Ignition switch ON
E61-35 Cruise control module (if equipped) 10 – 14 V Ignition switch ON
C51-3-1 Intake air temp. sensor 2.2 – 3.0 VIgnition switch ON, Sensor ambient
temp. : 20°C, 68°F
C51-3-2 Engine coolant temp. sensor 0.5 – 0.9 VIgnition switch ON, Engine coolant
temp. : 80°C, 176°F
C51-3-3 Knock sensor About 2.5 VWith engine running at idle after
warned up
C51-3-4 Power source 10 – 14 V Ignition switch ON
C51-3-5 Ground for MAF sensor – –
C51-3-6 Ground – –
C51-3-7 4WD switch0 – 1 VIgnition switch ON, Transfer lever :
4H or 4L range
10 – 14 VIgnition switch ON, Transfer lever :
2H range
C51-3-8 Manifold absolute pressure sensor 3.3 – 4.3 V Ignition switch ON and engine stops TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION
6-1-42 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
RESISTANCE CHECK
1) Disconnect couplers (1) from ECM/PCM with ignition switch
OFF.
2) Check resistance between each pair of terminals of discon-
nected couplers (1) as listed in following table. CAUTION:
Never touch terminals of ECM/PCM itself or connect volt-
meter or ohmmeter (2).
CAUTION:
Be sure to connect ohmmeter (2) probe from wire har-
ness side of coupler.
Be sure to turn OFF ignition switch for this check.
Resistance in table represents that when parts temper-
ature is 20°C (68°F).
TERMINALS CIRCUIT STANDARD
RESISTANCECONDITION
E61-9 and E61-2 Main relay 79 – 95 Ω–
E61-22 and C51-3-20 A/C fan motor relay (if equipped) 75 – 110 ΩBattery disconnected
and ignition switch ON
E61-23 and C51-3-20 Fuel pump relay 79 – 95 Ω–
C51-3-6 and Body ground Ground Continuity –
C51-3-17 and Body ground Ground Continuity –
C51-1-1 and Body ground Shift solenoid B (A/T) 11 – 15 Ω–
C51-1-2 and Body ground Shift solenoid A (A/T)
C51-1-4 and C51-3-4 IAC valve (stepper motor coil 2) 25.5 – 33.5 Ω–
C51-1-5 and C51-3-4 IAC valve (stepper motor coil 1)
C51-1-8 and Body ground TCC solenoid (A/T) 11 – 15 Ω–
C51-1-15 and C51-3-4 EVAP canister purge valve 28 – 35 Ω–
C51-1-16 and C51-3-4 IAC valve (stepper motor coil 4) 25.5 – 33.5 Ω–
C51-1-17 and C51-3-4 IAC valve (stepper motor coil 3)
C51-2-1 and C51-3-4 Fuel injector No.2 13 – 16 Ω–
C51-2-2 and C51-3-4 Fuel injector No.1
C51-2-4, C51-2-5 and E61-9 Heater of HO2S-1 5.0 – 6.4 Ω–
C51-2-7 and Body ground Ground Continuity –
C51-2-8 and C51-3-4 Fuel injector No.4 13 – 16 Ω–
C51-2-9 and C51-3-4 Fuel injector No.3
C51-2-12 and C51-3-4 EGR valve (stepper motor coil 4) 20 – 24 Ω–
C51-2-13 and C51-3-4 EGR valve (stepper motor coil 3)
C51-2-14 and C51-3-4 EGR valve (stepper motor coil 2)
C51-2-15 and C51-3-4 EGR valve (stepper motor coil 1)
C51-2-16, C51- 2-17 and
E61-9Heater of HO2S-2 11.7 – 14.3 Ω–
C51-2-21 and C51-3-4 Fuel injector No.6
13 – 16 Ω–
C51-2-22 and C51-3-4 Fuel injector No.5
6-1-116 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table B-1 Fuel Pump Circuit Inspection
WIRING DIAGRAM
INSPECTION
1. To ignition switch 4. Fuel pump relay
2. Main fuse 5. Fuel pump
3. Main relay 6. ECM (PCM)
CAUTION:
Check to make sure that connection is made between correct terminals.
Wrong connection can cause damage to ECM, wire harness etc.
Step Action Yes No
1 Fuel pump operation check :
1) Remove fuel filler cap.
2) Turn ON ignition switch.
Is fuel pump operation sound heard for 3 sec.
after ignition switch ON?Fuel pump circuit is in
good condition.Go to Step 2.
2 Fuel pump circuit check :
1) With ignition switch OFF, remove fuel pump
relay from connector.
2) Check for proper connection to relay at
each terminal.
3) If OK, using service wire, connect terminals
E07-7 and E07-8 of relay connector. (See
Fig.)
Is fuel pump heard to operate at ignition switch
ON?Go to Step 3.“BLU/BLK”, “PNK/BLK” or
“BLK” circuit open or fuel
pump malfunction.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-117
Fig. for Step 2
Table B-2 Fuel Injectors and Circuit Inspection
WIRING DIAGRAM
3 Fuel pump relay check :
1) Check fuel pump relay referring to “FUEL
PUMP RELAY INSPECTION” in Section
6E2.
Is it in good condition?“BLK/WHT” or “WHT/
GRN” circuit open or poor
E61-23 connection.
If wire and connection are
OK, substitute a known-
good ECM (PCM) and
recheck.Replace fuel pump relay. Step Action Yes No
1. Fuel pump relay connector
1. To ignition switch 4. Injector No.1 7. Injector No.4 10. ECM (PCM)
2. Main fuse 5. Injector No.2 8. Injector No.5
3. Main relay 6. Injector No.3 9. Injector No.6