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
6-1-124 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table B-6 A/C Condenser Fan Motor Relay Control System Inspection (If
Equipped)
WIRING DIAGRAM
INSPECTION
1. To ignition switch 3. A/C fuse 5. A/C condenser fan motor
2. Main fuse 4. A/C condenser fan motor relay 6. ECM (PCM)
WARNING:
Keep hands, tools, and clothing away from A/C condenser fan to help prevent personal injury. This
fan is electric and can come on whether or not the engine is running. The fan can start automatically
in response to the ECT sensor with the ignition switch in the “ON” position.
Step Action Yes No
1 1) Check DTC referring to “DTC CHECK” in this sec-
tion.
Is there any malfunction DTC?Go to applicable DTC
Diag. Flow Table.Go to Step 2.
2 1) Check A/C condenser fan for operation.
A/C condenser fan should be operated under follow-
ing condition A or B only.
A : When engine is running and A/C is operating.
B : When engine coolant temp. is 113°C (235°F) or
more with ignition switch ON.
Is check result as specified?This system is in
good condition.Go to Step 3.
3 1) Remove ECM (PCM) cover.
2) Check voltage between E61-22 terminal of ECM
(PCM) connected coupler and ground.
Other than conditions A and B in Step 2 :
10 – 14 V
Under condition A or B in Step 2 :
0 – 1 V
Is check result as specified?Fuse blown, “RED”,
“RED/BLK” or “RED/
BLU” circuit open,
malfunction of con-
denser fan motor or
relay.“YEL/GRN” circuit
open, “YEL/BLU” cir-
cuit open or short, or
relay malfunction.
If above are OK, sub-
stitute a known-good
ECM (PCM) and
recheck.
6A2-20 ENGINE MECHANICAL (H27 ENGINE)
12) Install oil pan and oil pump strainer.
Refer to “OIL PAN AND OIL PUMP STRAINER” in this sec-
tion.
13) Install cylinder head cover.
Refer to “CYLINDER HEAD COVER” in this section.
14) Install exhaust manifold.
Refer to “EXHAUST MANIFOLD” in this section.
15) Install radiator outlet pipe, radiator, cooling fan and water
hose.
Refer to “COOLING WATER PIPES OR HOSES”, “RADIA-
TOR” and “COOLING FAN AND FAN CLUTCH” in Section
6B.
16) Install throttle body and intake manifold.
Refer to “THROTTLE BODY AND INTAKE MANIFOLD” in
this section.
17) Adjust water pump drive belt tension.
Refer to “COOLING FAN BELT TENSION CHECK AND
ADJUSTMENT” in Section 6B.
18) Adjust power steering pump drive belt tension.
Refer to “POWER STEERING PUMP DRIVE BELT” in Sec-
tion 3B1.
19) Adjust accelerator cable play and A/T throttle cable play.
Refer to “ACCELERATOR CABLE ADJUSTMENT” and “A/T
THROTTLE CABLE ADJUSTMENT (A/T VEHICLE)” in Sec-
tion 6E2.
20) Check to ensure that all removed parts are back in place.
Reinstall any necessary parts which have not been rein-
stalled.
21) Refill engine with engine oil, referring to “ENGINE OIL
CHANGE” in Section 0B.
22) Refill cooling system referring to “COOLING SYSTEM
FLUSH AND REFILL” in Section 6B.
23) Refill front differential housing with gear oil if drained, refer-
ring to “MAINTENANCE SERVICE” in Section 7E.
24) Connect negative cable at battery.
25) Check ignition timing and adjust as necessary, referring to
“IGNITION TIMING CHECK AND ADJUSTMENT” in Section
6F2.
26) Verify that there is no fuel leakage, water leakage, oil leak-
age and exhaust gas leakage at each connection.
27) Check wheel alignment, referring to “STEERING ANGLE” in
Section 3A.
6A2-26 ENGINE MECHANICAL (H27 ENGINE)
Unit Repair Overhaul
Engine Assembly
REMOVAL
1) Release fuel pressure in fuel feed line. Refer to “FUEL
PRESSURE RELIEF PROCEDURE” in Section 6.
2) Disconnect negative (–) cable at battery.
3) Remove engine hood.
4) Drain engine oil.
5) Drain coolant.
6) Remove radiator, radiator fan shroud, cooling fan and radia-
tor reservoir. Refer to “COOLING FAN AND FAN CLUTCH”
and “RADIATOR” in Section 6B.
7) Disconnect accelerator cable (1) and A/T throttle cable (for
A/T vehicle) (2) from throttle body.
8) Remove strut tower bar and surge tank cover.
9) Disconnect IAT sensor coupler and MAF sensor coupler then
remove air cleaner upper case, intake air hose, intake air
pipe and surge tank pipe as a component.
10) Remove engine oil level gauge guide and A/T fluid level
gauge guide (for A/T vehicle).
11) Remove ignition coil covers.
12
ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-5
1. Air cleaner 22. Fuel level sensor 39. A/C controller (if equipped)
2. Intake air temp. sensor 23. Monitor connector (if equipped) 40. Data link connector/Immobilizer control mod-
ule (if equipped)
3. Mass air flow sensor 23-1. Diag. switch terminal 41. ABS control module
4. EVAP canister purge valve 23-2. Test switch terminal 42. Main relay
5. Throttle position sensor 23-3. Output duty select switch terminal 43. Ignition switch
6. Idle air control valve 23-4. Duty output terminal 44. Park/Neutral position switch in TR switch (A/T)
7. Camshaft position sensor 24. Fuel filter 45. Battery
8. EGR valve 25. Fuel pressure regulator 46. Starter magnetic switch
9. Manifold absolute pressure sensor
(if equipped)26. Immobilizer indicator lamp (if equipped) 47.“O/D OFF” lamp (A/T)
10. Fuel injector 27. Tank pressure control valve 48.“POWER” lamp (A/T)
11. PCV valve 28. EVAP canister 49. Lighting switch (A/T)
12. Ignition coil assembly 29. Knock sensor 50. Stop lamp switch (A/T)
13. Engine coolant temperature sensor 30. ECM/PCM (Engine control module/Powertrain con-
trol module)51. O/D cut switch (A/T)
14. Heated oxygen sensor
(bank 1 sensor 1) (if equipped)31. Malfunction indicator lamp 52. POWER/NORMAL change switch (A/T)
15. Heated oxygen sensor
(bank 2 sensor 1) (if equipped)32. Electric loads (rear defogger (if equipped), lighting) 53. 4WD low switch (A/T)
16. Heated oxygen sensor
(bank 1 sensor 2) (if equipped)33. Power steering pressure switch 54. Transmission range switch (A/T)
17. Heated oxygen sensor
(bank 2 sensor 2) (if equipped)34. Heater blower fan switch 55. Solenoid valve A (A/T)
18. Warm-up three way catalytic converter
(if equipped)35. Cruise control module 56. Solenoid valve B (A/T)
19. Three way catalytic converter
(if equipped)36. Vehicle speed sensor 57. TCC solenoid valve (A/T)
20. Crankshaft position sensor
(if equipped)37. Combination meter 58. A/T input speed sensor (A/T)
21. Fuel pump 38. A/C condenser fan relay (if equipped) 59. A/T vehicle (output) speed sensor (A/T)
6E2-8 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Electronic Control System
The electronic control system consists of 1) various sensors which detect the state of engine and driving condi-
tions, 2) ECM (PCM) which controls various devices according to the signals from the sensors and 3) various
controlled devices.
Functionally, it is divided into the following sub systems:
•Fuel injection control system
•Heated oxygen sensor heater control system (if equipped)
•Idle air control system
•Fuel pump control system
•Evaporative emission control system
•Ignition control system
•EGR system (if equipped)
Also, with A/T model, PCM controls A/T.
INFORMATION SENSORS CONTROLLED DEVICES OTHERS
1. IAT sensor a : A/C condenser fan motor relay (if equipped) A : Main fuse box
2. MAP sensor (if equipped) b : Ignition coil assemblies B : ECM (PCM)
3. Heated oxygen sensor (sensor 1) (if equipped) c : EVAP canister purge valve C : Data link connector
4. ECT sensor d : EGR valve (if equipped) D : Combination meter
5. TP sensor e : Idle air control valve E : Fuse box
6. MAF sensor f : Injectors F : EVAP canister
7. Camshaft position sensor (CMP sensor) g : Malfunction indicator lamp
8. ABS control module h : Fuel pump relay
9. Crankshaft position sensor (CKP sensor) (if equipped) i : Main relay
10. Power steering pressure switch (PSP switch) j : Oxygen sensor heater relay (if equipped)
11. CO adjusting resistor (if equipped)
12. Monitor connector (if equipped)
13. Transmission range switch (A/T)
14. Knock sensor
NOTE:
Above figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are
installed at the side of symmetry.
6E2-10 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
TERMINAL ARRANGEMENT OF ECM (PCM) CONNECTOR (VIEWED FROM HARNESS SIDE)
1. Fuel injector No.1 17.“O/D OFF” lamp (A/T) 34. Power steering pressure switch
2. Fuel injector No.2 18.“POWER” lamp (A/T) 35. Stop lamp switch (Brake pedal switch)
3. Fuel injector No.3 18-1.“4WD” lamp (4WD) 36. Lighting switch
4. Fuel injector No.4 18-2. 4WD air pump assembly (4WD) 37. Rear defogger switch (if equipped)
4-1. Fuel injector No.5 19. 4WD switch (4WD) 38. Heater blower motor (if equipped)
4-2. Fuel injector No.6 20. Power/Normal change switch (A/T) 39. A/C control module (amplifier)
5. EGR valve (if equipped) 21. O/D cut switch (A/T) 40. ABS control module
6. Idle air control 21-1. 4WD low switch (4WD) 41. Heated oxygen sensor-1 (Bank1) (if equipped)
7. EVAP canister purge valve 22. Main relay 41-1. Heated oxygen sensor-1 (Bank2) (if equipped)
8. Ignition coil for No.1 23. Transmission range switch (Park/Neutral
Position Switch) or clutch pedal position switch42. Heater oxygen sensor-2 (Bank1) (if equipped)
8-1. Ignition coil for No.2 24. Starter magnetic switch 42-1. Heater oxygen sensor-2 (Bank2) (if equipped)
9. Ignition coil for No.3 24-1. Cruise control module (if equipped) 43. Intake air temp. sensor
9-1. Ignition coil for No.4 25. Vehicle speed sensor 44. Engine coolant temp. sensor
10. Ignition coil for No.5 26. Combination meter 45. Throttle position sensor
10-1. Ignition coil for No.6 27. Data link connector 46. CO adjusting resistor (if equipped)
11. Fuel pump relay 28. TCC solenoid (A/T) 47. Manifold absolute pressure sensor (if
equipped)
12. Fuel pump 29. Shift solenoid-B (A/T) 48. Mass air flow sensor
13. A/C condenser fan relay (if equipped) 30. Shift solenoid-A (A/T) 49. Camshaft position sensor
14. A/C condenser fan motor (if equipped) 31. Transmission range switch (sensor) (A/T) 50. Crankshaft position sensor (if equipped)
15. Knock sensor 32. A/T input speed sensor (A/T) 51. Monitor connector (if equipped)
16. Malfunction indicator lamp 33. A/T vehicle (output) speed sensor (A/T) 52. Engine control module
(Powertrain control module)
TERMINAL CIRCUIT TERMINAL CIRCUIT TERMINAL CIRCUIT
E61-1 Power source for CO adjusting resistor
(if equipped)E61-13 Data link connector E61-25—
E61-2 Power source for back up E61-14 Test switch terminal (if equipped) E61-26—
E61-3—E61-15 Rear defogger switch (if equipped) E61-27—
E61-4 Cruise control module
(Throttle opening signal)E61-16 Heater blower switch E61-28—
E61-5 Duty output terminal (if equipped) E61-17 A/C signal (if equipped) E61-29 Diag. switch terminal (if equipped)
E61-6 Tachometer E61-18—E61-30 ABS control module (if equipped)
E61-7 MIL (“SERVICE INGINE SOON” lamp) E61-19“4WD” lamp E61-31 Power/Normal change switch (A/T)
E61-8 A/C cut signal (if equipped) E61-20“O/D OFF” lamp (A/T) E61-32 Lighting switch
E61-9 Main relay E61-21“POWER” lamp (A/T) E61-33 O/D cut switch (A/T)
E61-10 CO adjusting resistor (if equipped) E61-22 A/C fan motor relay (if equipped) E61-34 Stop lamp switch (Brake pedal switch)
E61-11—E61-23 Fuel pump relay E61-35 Cruise control module (if equipped)
E61-12—E61-24 Ground for CO adjusting resistor (if
equipped)