1A-2 HEATER AND VENTILATION
General Description
The heater, an in and out air selectable-type hot water heater, is so constructed that it is possible to assure an
agreeable ventilation at all times by providing the ventilator air outlets at the center and both sides (right and left)
of the instrument panel, the hot air outlet at a place close to the feet, and the defroster air outlets at places, right
and left, along the windshield glass.
The heater and ventilation consist of the following parts.
1. Side ventilator outlet 4. Heater unit 7. Heater control lever assembly 10. Rear duct
2. Side defroster outlet 5. Defroster duct 8. Heater mode control switch
3. Center ventilator outlet 6. Ventilator duct 9. Blower unit
10
1B-4 AIR CONDITIONING (OPTIONAL)
Major Components And Location
[A] : Dual A/C model 6. Receiver/dryer 13. Suction pipe 20. Ventilation air
[B] : Single A/C model 7. Front expansion valve 14. Discharge pipe 21. Rear A/C air
1. Front cooling unit 8. Heater unit 15. Recirculation air 22. Room air
2. Front A/C evaporator 9. Rear A/C unit 16. Fresh air 23. Solenoid valve
3. Front blower fan motor 10. Rear blower fan motor 17. Defroster air 24. Rear A/C evaporator
4. Compressor 11. Rear expansion valve 18. Demister air
5. Condenser assembly 12. Liquid pipe 19. Foot air
17 17
18 18
16 [A]
[B]15
21
2211
23
9
24
10 141320
21
19 19
4 12
6 312
78
17 17
18 18
16
15
20
19 19 1
2
8 5
7
12
6
513
4 14
AIR CONDITIONING (OPTIONAL) 1B-7
Cool air does not
come out or insuffi-
cient cooling (A/C sys-
tem normal operative)Insufficient or excessive charge of refrigerant Check charge of refrigerant.
Refrigerant leak in system Check system for leaks.
Condenser clogged Check condenser.
A/C evaporator clogged or frosted Check A/C evaporator.
A/C evaporator temperature sensor (A/C evap-
orator thermistor) faultyCheck A/C evaporator tempera-
ture sensor (A/C evaporator ther-
mistor).
A/C controller faulty Check A/C controller.
Expansion valve faulty Check expansion valve.
Drive belt slipping Check or replace drive belt.
Magnetic clutch faulty Check magnetic clutch.
Cool air does not
come out or insuffi-
cient cooling (A/C sys-
tem normal operative)Compressor faulty Check compressor.
Air in A/C system Replace condenser dryer, and then
perform evacuation and charging.
Air leaking from cooling unit or air duct Repair as necessary.
Heater and ventilation system faulty Check air inlet box assembly.
Check heater control lever assem-
bly.
Check heater assembly.
Blower motor faulty Check blower motor.
Excessive compressor oil existing in A/C sys-
temPull out compressor oil in A/C sys-
tem circuit, and replace compres-
sor.
Cool air does not
comes out only inter-
mittentlyWiring connection faulty Repair as necessary.
Expansion valve faulty Check expansion valve.
Excessive moisture in A/C system Replace condenser dryer, and then
perform evacuation and charging.
A/C controller faulty Check A/C controller.
Magnetic clutch faulty Check magnetic clutch.
Excessive charge of refrigerant Check charge of refrigerant.
Cool air comes out
only at high speedsCondenser clogged Check condenser.
Insufficient charge of refrigerant Check charge of refrigerant.
Air in A/C system Replace condenser dryer, and then
perform evacuation and charging.
Drive belt slipping Adjust or replace drive belt.
Compressor faulty Check compressor.
Cool air does not
comes out only at high
speedsExcessive charge of refrigerant Check charge refrigerant.
A/C evaporator frosted Check A/C evaporator.
Check A/C thermistor.
Insufficient velocity of
cooled airA/C evaporator clogged or frosted Check A/C evaporator.
Air leaking from cooling unit or air duct Repair as necessary.
Blower motor faulty Check blower motor.
Wiring or grounding faulty Repair as necessary. Condition Possible Cause Correction
1B-12 AIR CONDITIONING (OPTIONAL)
Performance diagnosis table
HIGH PRESSURE GAUGE
LOW PRESSURE GAUGE
THERMOMETER AT CENTER DUCT
Condition Possible Cause Correction
Pressure high
(“A” area of high side
graph)Refrigerant overcharged Recharge.
Expansion valve frozen or clogged Check expansion valve.
Clogged refrigerant passage of high side Clean or replace.
Condenser cooling fan malfunction (Insufficient cooling
of condenser)Check condenser cooling fan.
Dirty or bent condenser fins (Insufficient cooling of con-
denser)Clean or repair.
Compressor malfunction (Insufficient oil etc.) Check compressor.
Engine overheat Check engine cooling system.
Pressure low
(“B” area of high side
graph)Insufficient refrigerant (Insufficient charge or leakage) Check for leakage, repair if necessary
and recharge.
Expansion valve malfunction (valve opens too wide) Check expansion valve.
Compressor malfunction (Insufficient compression) Check compressor.
Condition Possible Cause Correction
Pressure high
(“C” area of low side
graph)Expansion valve malfunction (valve opens too wide) Check expansion valve.
Compressor malfunction (Insufficient compression) Check compressor.
Pressure low
(“D” area of low side
graph)Insufficient refrigerant (Insufficient charge or leakage) Check for leakage, repair if necessary
and recharge.
Expansion valve malfunction (valve opens too narrow) Check expansion valve.
Clogged refrigerant passage (crashed pipe) Repair or replace.
Condition Possible Cause Correction
Outlet air temperature at
center duct is high
(Crossing point is in area
“E”)Insufficient or excessive charge of refrigerant Check refrigerant pressure.
Dirty or bent A/C evaporator fins Clean or repair.
Air leakage from cooling (heater) unit or air duct Repair or replace.
Malfunctioning, switch over function of damper in cool-
ing (heater) unitRepair or replace.
Compressor malfunction Check compressor.
Outlet air temperature at
center duct is low
(Crossing point is in area
“F”)Insufficient air volume from center duct (Heater blower
malfunction)Check blower motor and fan.
Compressor malfunction Check compressor.
NOTE:
If ambient temperature is within 30 - 35 °C (85 - 95 °F), it is possible to do using “DETAIL DIAGNOSIS
TABLE” in this section for detail diagnosis.
1B-14 AIR CONDITIONING (OPTIONAL)
Wiring Circuit
ACG
LT GRN
PNK
PNK
BLKORN
BLK
YEL/GRNRED/BLKBLK/WHT
BLU/WHTPNK/BLK
PNK/GRN
RED/BLK
WHT/RED
YEL/GRN
YEL/BLU
A/C
RED/BLU
RED/BLU
RED/BLKBLK
BLU/ORN
BLU/WHT
BLU/WHT
PNK
PNK/BLU
BLK
PNK/WHT
YEL/BLK
GRY/WHT
GRN/BLK
BLK/WHT
RED/BLK
YEL/GRN
BLK
BLK
BLK
YEL/BLK
YEL/GRN
YEL/GRNBLU/GRN
BLU/YELBLUBLU/BLK
BLU/BLK
17
21
22 18
16
15
19
2026 25 24 23
14
12
29
3
4
7
33 30
31
32
28
27
1213
10
11
35 349
856
A
1. Front blower motor main relay 10. Compressor relay 19. Battery 28. Solenoid valve relay
2. Front blower motor 11. Compressor 20. Generator 29. Rear blower motor relay
3. Front blower motor resistor 12. Condenser cooling fan motor
relay21. Ignition main fuse 60 A 30. Rear blower motor resistor
4. Front blower motor switch 13. Condenser cooling fan motor 22. Heater/A/C main fuse 60 A 31. Rear blower motor
5. A/C controller 14. Fuse box 23.“IG METER” fuse 20 A 32. Rear blower motor switch
6. ECM (PCM) 15.“A/C” fuse 25 A 24.“REAR DEFG” fuse 25 A 33. Rear A/C main switch
7. Heater mode control switch 16. Ignition switch 25.“REAR BLOW” fuse 20A 34. Rear A/C evaporator temperature con-
troller
8. Dual (refrigerant) pressure switch 17. Main fuse box 26.“FRONT BLOW” fuse 30A 35. Rear A/C evaporator temperature sensor
9. A/C evaporator thermistor
(A/C evaporator temperature sensor)18. Battery main fuse 100 A 27. Solenoid valve [A] : Rear A/C wiring circuit (if equipped)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-37
TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION
E61-1Power source for CO adjusting
resistor (if equipped)10 – 14 V Ignition switch ON
E61-2 Power source for back up 10 – 14 V Ignition switch ON and OFF
E61-3 – – –
E61-4Cruise control module
(throttle opening signal)
(if equipped)Ignition switch ON, Voltage varies as specified at figure in
cruise control diagnosis of Section 8E while throttle valve is
opened gradually.
E61-5Duty output terminal
(vehicle with monitor connector)0 – 1 V Ignition switch ON
E61-6 Tachometer 0 – 1 V Ignition switch ON, engine stops
E61-7Malfunction indicator lamp
(“SERVICE ENGINE SOON” lamp)0 – 2.5 V Ignition switch ON, engine stops
10 – 14 V Engine running
E61-8 A/C cut signal (if equipped)0 – 1.5 V A/C is not operating
10 – 14 V A/C is operating
E61-9 Main relay10 – 14 V Ignition switch OFF
0 – 2 VIgnition switch ON or for 4 seconds
after ignition switch OFF
E61-10 CO adjusting resistor (if equipped) – –
E61-11 – – –
E61-12Data link connector (5V)
(Vehicle with monitor connector)4 – 6 V Ignition switch ON
E61-13 Data link connector (12V) 10 – 14 V Scan tool not connected to DLC
E61-14Test switch terminal
(Vehicle with monitor connector)10 – 14 V Ignition switch ON
E61-15 Rear defogger switch (if equipped)0 – 1.5 VIgnition switch ON, rear defogger
switch OFF
10 – 14 VIgnition switch ON, rear defogger
switch
E61-16 Heater blower switch10 – 14 VIgnition switch ON, heater blower
switch OFF
0 – 1.5 VIgnition switch ON, heater blower
switch ON
E61-17 A/C signal (if equipped)10 – 14 VIgnition switch ON, A/C switch or
heater blower switch OFF
0 – 1 VIgnition switch ON, A/C switch ON
and heater blower switch ON
E61-18 – – –
E61-19 “4WD” lamp0 – 1 VIgnition switch ON, Transfer lever :
4H or 4L range
10 – 14 VIgnition switch ON, Transfer lever :
2H range
E61-20 “O/D OFF” lamp (A/T vehicle)0 – 1 VFor 4 sec. after ignition switch ON
or overdrive cut switch ON
10 – 14 VAfter 4 sec. from ignition switch ON
and overdrive cut switch OFF
E61-21 “POWER” lamp (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
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-123
Table B-5 A/C Signal Circuits Inspection (If Equipped)
WIRING DIAGRAM
INSPECTION
1. A/C control module (amplifier)
2. ECM (PCM)
Step Action Yes No
1 Check A/C Signal Circuit.
1) Check voltage at terminal E61-17 with ignition
switch ON.
A/C signal circuit specification :
A/C switch and/or heater blower switch OFF (A/
C is not operating) : 10 – 14 V
Both A/C switch and heater blower switch ON :
0 – 1.5 V
Are check result as specified?Go to Step 2.“YEL/BLK” circuit open or
short, Evaporative tem-
perature is below 1°C
(34°F) or faulty A/C sys-
tem.
2 Check A/C Cut Signal Circuit.
1) Check voltage at terminal E61-8.
A/C cut signal specification :
While engine running and A/C switch and/or
heater blower switch OFF
(A/C is not operating) : 0 – 1.5 V
While engine running at idle speed and both A/
C switch and heater blower switch ON
(A/C is operating) : 10 – 14 V
Are check result as specified?A/C control signal cir-
cuits are in good con-
dition.“GRY/WHT” circuit open
or short, Poor perfor-
mance of ECT sensor, TP
sensor, Engine start sig-
nal inputted or A/C ampli-
fier malfunction.
If none of the above
exists, substitute a
known-good ECM (PCM)
and recheck.
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)