6B-4 ENGINE COOLING
DIAGNOSIS
DIAGNOSIS TABLE
Condition Possible Cause Correction
Engine overheats
(It is in case that radia-
tor fan operates)Loose or broken water pump belt Adjust or replace.
Not enough coolant Check coolant level and add as
necessary.
Faulty thermostat Replace.
Faulty water pump Replace.
Dirty or bent radiator fins Clean or remedy.
Coolant leakage on cooling system Repair.
Clogged radiator Check and replace radiator as nec-
essary.
Faulty radiator cap Replace.
Improper ignition timing Adjust.
Dragging brakes Adjust brake.
Slipping clutch Adjust or replace.
Poor charge battery Check and replace as necessary.
Poor generation generator Check and repair.
ECT sensor faulty Check and replace as necessary.
Radiator cooling fan relay No.2 and/or No.3
faultyCheck and replace as necessary.
ECM faulty Check and replace as necessary.
Wiring or grounding faulty Repair and necessary.
Equipped with too much electric load part Dismount.
Radiator cooling fan motor faulty Check and replace as necessary.
Engine overheats
(It is in case that radia-
tor fan won’t operates)Fuse blown Check “RADTR fan” fuse and
check for short circuit to ground.
Radiator cooling fan relay No.1 Check and replace as necessary.
ECT sensor faulty Check and replace as necessary.
Radiator cooling fan motor faulty Check and replace as necessary.
Wiring or grounding faulty Repair as necessary
ECM faulty Check and replace as necessary.
ENGINE AND EMISSION CONTROL SYSTEM 6E1-5
AIR INTAKE SYSTEM
The main components of the air intake system are air cleaner (1), air cleaner outlet hose (2), throttle body (3),
idle air control valve (4) and intake manifold (5).
The air (by the amount corresponding to the throttle valve (6) opening and engine speed) is filtered by the air
cleaner (1), passes through the throttle body (3), is distributed by the intake manifold (5) and finally drawn into
each combustion chamber.
When the idle air control valve (4) is opened according to the signal from ECM, the air (7) bypasses the throttle
valve (6) through bypass passage and is finally drawn into the intake manifold (5).
1. Air Cleaner 16. Immobilizer indicator lamp (if equipped) 31. Monitor connector (vehicle without immobi-
lizer indicator lamp)
2. EVAP canister purge valve 17. Knock sensor (if equipped) 31-1. Diagnosis switch terminal (vehicle without
immobilizer indicator lamp)
3. IAT sensor 18. ECT sensor 31-2. Test switch terminal (vehicle without immobi-
lizer indicator lamp)
4. TP sensor 19. CMP sensor 31-3. Duty output terminal (vehicle without immobi-
lizer indicator lamp)
5. IAC valve 20. CKP sensor 32. Stop lamp
6. MAP sensor 21. VSS 33. Stop lamp switch
7. EGR valve (if equipped) 22. Radiation fan 34. ECM
8. EVAP canister 23. Malfunction indicator lamp in combination meter 35. Barometric pressure sensor (if equipped)
9. Tank pressure control valve (built-in fuel pump) 24. Park/Neutral position switch (A/T) 36. Battery
10. Fuel pump (with pressure regulator) 25. Ignition switch 37. CO adjusting resistor (if equipped)
11. Fuel level sensor (vehicle with immobilizer indi-
cator lamp)26. Starter magnetic switch 38. A/C compressor clutch (if equipped)
12. Ignition coil assembly 27. TCM 39. A/C switch (if equipped)
13. Fuel injector 28. Transmission range switch (A/T) 40. A/C evaporator temp. sensor (if equipped)
14. Heated Oxygen Sensor (HO2S)-1
(if equipped)29. DLC 41. Immobilizer control module (if equipped)
15. Heated Oxygen Sensor (HO2S)-2
(if equipped)30. Electric load 42. Main relay
54
2
1
6
3
7
6E1-8 ENGINE AND EMISSION CONTROL SYSTEM
ENGINE & EMISSION CONTROL INPUT/OUTPUT TABLE
INPUTOUTPUT
ELECTRIC CONTROL DEVICE
FUEL LEVEL SENSOR (VEHICLE WITH IMMOBILIZER INDICATOR LAMP) For detecting fuel level DIAGNOSIS SWITCH (VEHICLE WITHOUT IMMOBILIZER INDICATOR LAMP)
BAROMETRIC PRESSURE SENSOR (VEHICLE WITH EGR VALVE)
STOP LAMP SWITCH
START SWITCH
IGNITION SWITCH
LIGHTING SWITCH
REAR DEFOGGER SWITCH
BLOWER SWITCH
A/C SWITCH
A/C EVAP TEMP. SENSOR
VSS
HEATED OXYGEN SENSOR-1
(VEHICLE WITH EGR VALVE)
HEATED OXYGEN SENSOR-2
(VEHICLE WITH IMMOBILIZER INDICATOR LAMP)For detecting deterioration of
three way catalytic convertor
IAT SENSOR
ECT SENSOR
TP SENSOR
MAP SENSOR
CMP SENSOR
CKP SENSOR
TEST SWITCH TERMINAL
(VEHICLE WITHOUT IMMOBILIZER INDICATOR LAMP)
KNOCK SENSOR (VEHICLE WITH EGR VALVE)
FUEL PUMP RELAY
FUEL INJECTOR
HO2S HEATER
IAC VALVE
IGNITION COIL WITH IGNITER
EGR VALVE (IF EQUIPPED)
EVAP CANISTER PURGE VALVE
A/C COMPRESSOR CLUTCH
RADIATOR FAN RELAY
MIL
MAIN RELAY
TRANSMISSION CONTROL MODULE SIGNAL FROM SENSOR, SWITCH AND CONTROL MODULE
6E1-10 ENGINE AND EMISSION CONTROL SYSTEM
1. CKP sensor 20. Blank 39. Ignition coil assembly (for No.1 and No.4 spark plugs)
2. CMP sensor 21. A/C switch 40. Ignition coil assembly (for No.2 and No.3 spark plugs)
3. VSS 22. A/C pressure switch 41. Stop lamp switch
4. MAP sensor 23. Immobilizer control module 42. Stop lamp
5. Knock sensor (if equipped) 24. Data link connector 43. Lighting switch
6. TP sensor 25. Injector No.1 44. Position lamp
7. ECT sensor 26. Injector No.2 45. Rear defogger switch
8. IAT sensor 27. Injector No.3 46. Rear defogger
9. Heated oxygen sensor-1 (if equipped) 28. Injector No.4 47. A/C compressor clutch (if equipped)
10. Heated oxygen sensor-2 (if equipped) 29. IAC valve 48. Ignition switch
11. A/C evaporator temp. sensor 30. EVAP canister purge valve 49. Main relay
12. Combination meter 31. Fuel pump relay 50. Transmission range switch (A/T)
13. Fuel level sensor (vehicle with immobilizer
indicator lamp)32. Fuel pump 51. Starting motor
14. TCM 33. Radiator fan relay 52. Shield wire
15. Transmission range switch 34. Radiator fan motor 53. Main fuse
16. ABS control module 35. EGR valve (if equipped) 54. Barometric pressure sensor
17. CO adjusting resistor (if equipped) 36. Malfunction indicator lamp 55. Immobilizer indicator lamp (if equipped)
18. Heater fan motor 37. Tachometer 56. Engine ground
19. Heater fan switch 38. Monitor connector (vehicle without immo-
bilizer indicator lamp)57. Body ground
6E1-12 ENGINE AND EMISSION CONTROL SYSTEM
1. CKP sensor 20. Blank 39. Ignition coil assembly (for No.1 and No.4 spark plugs)
2. CMP sensor 21. A/C switch 40. Ignition coil assembly (for No.2 and No.3 spark plugs)
3. VSS 22. A/C pressure switch 41. Stop lamp switch
4. MAP sensor 23. Immobilizer control module 42. Stop lamp
5. Knock sensor (if equipped) 24. Data link connector 43. Lighting switch
6. TP sensor 25. Injector No.1 44. Position lamp
7. ECT sensor 26. Injector No.2 45. Rear defogger switch
8. IAT sensor 27. Injector No.3 46. Rear defogger
9. Heated oxygen sensor-1 (if equipped) 28. Injector No.4 47. A/C compressor clutch (if equipped)
10. Blank 29. IAC valve 48. Ignition switch
11. A/C evaporator temp. sensor 30. EVAP canister purge valve 49. Main relay
12. Combination meter 31. Fuel pump relay 50. Transmission range switch (A/T)
13. Fuel level sensor (vehicle with immobilizer
indicator lamp)32. Fuel pump 51. Starting motor
14. TCM 33. Radiator fan relay 52. Shield wire
15. Transmission range switch 34. Radiator fan motor 53. Main fuse
16. ABS control module 35. EGR valve (if equipped) 54. Barometric pressure sensor
17. CO adjusting resistor (if equipped) 36. Malfunction indicator lamp 55. Immobilizer indicator lamp (if equipped)
18. Heater fan motor 37. Tachometer 56. Engine ground
19. Heater fan switch 38. Monitor connector (vehicle without immo-
bilizer indicator lamp)57. Body ground
ENGINE AND EMISSION CONTROL SYSTEM 6E1-13
ECM TERMINAL ARRANGEMENT TABLE
For TYPE A (Refer to NOTE in page “ECM INPUT/OUTPUT CIRCUIT DIAGRAM” for applicable model.)
CONNEC-
TORTERMINAL WIRE COLOR CIRCUITCONNEC-
TORTERMINAL WIRE COLOR CIRCUIT
C421 BLK/ORN Ground for ECM
C4112––
2 BLK Ground for drive circuit 13–Heated oxygen sensor-2
3 BLK/ORN Ground for drive circuit 14 LT BLU“D”, “2”, “L”-range ID-UP signal
4 BLU/BLK Canister purge valve 15 RED“R”-range signal
5 WHT/BLK Coolant temp. signal output 16 YEL/GRN A/C SW signal
6 GRN/RED IAC valve 17 BRN/YEL EGR valve (stepper motor coil 4)
7 RED/BLU Heater of HO2S-1 18 BLU Radiator fan relay 1
8 BLU/ORN No.4 fuel injector 19 PNK Fuel pump relay
9 BLU/YEL No.1 fuel injector 20––
10 ORN Ground for sensor circuit 21 PPL Throttle opening signal output for A/T
11 RED/YEL CMP sensor 22 YEL/RED Fuel level gauge
12 RED Knock sensor (if equipped) 23 BLK/WHT TCM serial data line
13 WHTHeated oxygen sensor-1
(if equipped)
24––
CO adjusting resistor
(if equipped)
14 LT GRN Coolant temp. sensor
15 LT GRN/BLK Intake air temp. sensor
G021 PPL/WHT Malfunction indicator lamp
16 WHT/GRN Test switch terminal (if equipped) 2 PPL Vehicle speed sensor
17 RED/BLK Electric load (+) 3 PPL/YEL Radiator fan relay 2
18 PNK/GRN A/C switch 4––
19 GRN/WHTIG coil assembly for No.2 and 3 spark
plugs5 BLU Data link connector
20 GRN/YELIG coil assembly for No.1 and 4 spark
plugs6 BLK/WHT Ignition switch signal
21 BLU/WHT No.2 fuel injector 7 YEL Data link connector
22 GRY/RED Power supply for sensor 8––
23 YEL/BLK CKP sensor (+) 9 GRN/WHTStop lamp switch (Brake pedal
switch)
24––10 ORN GND for sensor
25–Ground for sensor shield wire 11––
26 RED/WHT MAP sensor 12 PNKImmobilizer indicator lamp
(if equipped)
27 PPL/WHTDiagnosis switch terminal
(if equipped)13 PNK/BLU Electrical load (-)
28 PNK/BLU Duty output terminal (if equipped) 14 WHT/BLK A/C evaporator temp. sensor
29 BRN Heater of HO2S-2 15––
30 GRN/BLK Heated oxygen sensor-2 16 BRN Tachometer signal
31 BLU/RED No.3 fuel injector 17 WHT/RED Backup power source
C411 PNK/BLK A/C compressor clutch
2 GRN EGR valve (stepper motor coil 1)
3 GRY/BLU Throttle position (TP) sensor
4–Heater of HO2S-2
5 BLK/RED Power source
6 BLK/RED Power source
7 BLK/YEL Engine start signal
8 WHT/RED EGR valve (stepper motor coil 3)
9 GRN/ORN EGR valve (stepper motor coil 2)
10 BRN/WHT Ground for main relay
11––
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
NOTE:
For abbreviation of wire color, refer to Section 0A.
6E1-14 ENGINE AND EMISSION CONTROL SYSTEM
For TYPE B (Refer to NOTE in page “ECM INPUT/OUTPUT CIRCUIT DIAGRAM” for applicable model.)
CONNEC-
TORTERMINAL WIRE COLOR CIRCUITCONNEC-
TORTERMINAL WIRE COLOR CIRCUIT
C421 BLK/ORN Ground for ECM
C4112––
2 BLK Ground for drive circuit 13––
3 BLK/ORN Ground for drive circuit 14 PPL/WHT Diagnosis switch terminal
4 BLU/BLK Canister purge valve 15 WHT/GRN Test switch terminal
5––16 YEL/GRN A/C SW signal
6 GRN/RED IAC valve 17 RED/YEL
Electric load (+)
7 RED/BLU Heater of HO2S-1 18 BLU Radiator fan relay 1
8 BLU/ORN No.4 fuel injector 19 PNK Fuel pump relay
9 BLU/YEL No.1 fuel injector 20 BLK/YEL
Cranking signal
10 ORN Ground for sensor circuit 21 GRN/WHTStop lamp switch (Brake pedal
switch)
11 RED/YEL CMP sensor 22 PPL Vehicle speed sensor
12 Or Grand for shield wire 23––
13 WHTHeated oxygen sensor-1
(if equipped)
24––
CO adjusting resistor
(if equipped)
14 LT GRN Coolant temp. sensor
15 LT GRN/BLK Intake air temp. sensor
G021 WHT/BLK A/C evaporator temp. sensor
16 GRY/BLU Throttle position (TP) sensor 2 RED“R” range signal
17 WHT/RED EGR valve (stepper motor coil 3) 3––
18 GRY EGR valve (stepper motor coil 1) 4––
19 GRN/WHTIG coil assembly for No.2 and 3 spark
plugs5 WHT/BLK Engine coolant temp. signals output
20 GRN/YELIG coil assembly for No.1 and 4 spark
plugs6 GRN/RED“D”, “2”, “L” range ID-UP signal
21 BLU/WHT No.2 fuel injector 7 YEL Data link connector
22 GRY/RED Power supply for sensor 8––
23 YEL/BLK CKP sensor (+) 9 PPL/WHT Malfunction indicator lamp
24––10––
25 RED Knock sensor (if equipped) 11 BLU
Data link connector
26 RED/WHT MAP sensor 12––
27––13 PNK/BLU Electrical load (-)
28 BRN/YEL EGR valve (stepper motor coil 4) 14 ORN Ground for sensor
29 GRN/ORNEGR valve (stepper motor coil 2)
15 PPL
Throttle opening signal output for
A/T
30 PNK/GRN A/C switch 16 BRN Tachometer signal
31 BLU/RED No.3 fuel injector 17––
C411 PNK/BLK A/C compressor clutch
2––
3––
4––
5 BLK/RED Power source for drive circuit
6 BLK/RED Power source for main circuit
7 WHT/RED Power source for memory circuit
8 PNK/BLU Duty signal output terminal
9 GRN/RED Radiator fan drive relay No.2
10 BRN/WHT Ground for main relay
11 BLK/WHT
Ignition switch signal
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
NOTE:
For abbreviation of wire color, refer to Section 0A.
6G-2 CRANKING SYSTEM
GENERAL DESCRIPTION
CRANKING CIRCUIT
DIAGNOSIS
DIAGNOSIS TABLE
Possible symptoms due to starting system trouble would be as follows:
Starting motor does not run (or runs slowly)
Starting motor runs but fails to crank engine
Abnormal noise is heard
Proper diagnosis must be made to determine exactly where the cause of each trouble lies.....in battery, wiring
harness, (including starting motor switch), starting motor or engine.
Do not remove motor just because starting motor does not run. Check following items and narrow down scope
of possible causes.
1) Condition of trouble
2) Tightness of battery terminals (including ground cable connection on engine side) and starting motor termi-
nals
3) Discharge of battery
4) Mounting of starting motor
1. Pinion drive lever 5. Plunger 9. Blank
2. Pinion & Over-running clutch 6. Magnetic switch contacts 10. A/T: Transmission range switch (shift lever switch)
3. Magnetic switch 7. Pull-in coil 11. Ignition & Starter switch
4. Hold-in coil 8. Starting motor 12. Battery