2003 TOYOTA 4RUNNER heater

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
The air conditioning filter is behind the
glove box.
The air conditioning filter may clog af-
ter long use. The filter may need to be
replaced if the air flow of the air condi-
tioning and heater experiences extreme
reductions in operating efficiency, or if
the windows begin to fog up easily.
To maintain the air conditioning efficiency,
inspect and replace the air conditioning
filter according to the maintenance sched-
ule. (For scheduled maintenance informa-
tion, please refer to the “Scheduled Main-
tenance Guide” or “Owner ’s Manual
Supplement”.)1. Open the glove box. Remove the
screw with a Phillipshead screw-
driver and slide the hook as shown.2. Push each side of the glove box todisconnect the claws.
Checking and replacing the
air conditioning filter

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
Ty p e A
Ty p e B
Ty p e CGood Blown
Good
Good
Blown
Blown
If the headlights or other electrical
components do not work, check the
fuses. If any of the fuses are blown,
they must be replaced.
See “Fuse locations” on page 318 in Sec-
tion 71 for locations of the fuses.
Turn the ignition switch and inoperative
component off. Pull a suspected fuse
straight out and check it.
Determine which fuse may be causing the
problem. The lid of the fuse box shows
the name of the circuit for each fuse. See
page 356 in Section 8 of this manual for
the functions controlled by each circuit. Type A fuses can be pulled out by using
the pullout tool. The location of the pull
out tool is shown in the illustration.
If you are not sure whether the fuse has
blown, try replacing the suspected fuse
with one that you know is good.
If the fuse has blown, push a new fuse
into the clip.
Only install a fuse with the amperage rat-
ing designated on the fuse box lid.
If you do not have a spare fuse, in an
emergency you can pull out the “PWR
OUTLET” or “HEATER NO.2” fuse, which
may be dispensable for normal driving,
and use it if its amperage rating is the
same.
If you cannot use one of the same amper-
age, use one that is lower, but as close
as possible to the rating. If the amperage
is lower than that specified, the fuse
might blow out again but this does not
indicate anything wrong. Be sure to get
the correct fuse as soon as possible and
return the substitute to its original clip.
It is a good idea to purchase a set of
spare fuses and keep them in your ve-
hicle for emergencies.
Checking and replacing fuses

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
Instrument panel
4. AC115V INV 15 A: AC inverter
5. FR FOG 15 A: Front fog lights
6. OBD 7.5 A: Onboard diagnosis sys-
tem
7. HEAD (LO RH) 10 A: Righthand headlight (low beam)
8. HEAD (LO LH) 10 A: Lefthand head-
light (low beam)
9. HEAD (HI RH) 10 A: Righthand head- light (high beam)
10. HEAD (HI LH) 10 A: Lefthand head- light (high beam) 11. EFI NO.2 10 A:
Multiport fuel injection
system/s equential multiport fuel injec-
tion system
12. HEATER NO.2 7.5 A: Air conditioning
system
13. AIRSUS NO.2 10 A: Rear height con-
trol air suspension
14. SEAT HEATER 25 A: Seat heaters
15. DEFOG 30 A: Rear window defogger,
multiport fuel injection system/sequen-
tial multiport fuel injection system
16. MIR HEATER 10 A: Outside rear view
mirror heater
17. DOME 10 A: Interior light, personal
lights, wireless remote control system,
door courtesy lights, rear seat audio
system, g auge and meter, vanity lights,
instrument panel lights, running board
lights, multiplex communication system
18. RADIO NO.1 20 A: Audio system, nav-
igation system
19. ECUB 10 A: Antilock brake system,
navigation system, traction control sys-
tem (twowheel drive models), active
traction control system (fourwheel
drive models), vehicle stab ility control
system, air c onditioning system, multi-
plex communication system, theft deter-
rent system 20. ALTS 7.5 A:
Charging system
21. HORN 10 A: Horns
22. A/F HEATER 15 A: No circuit
23. TRNHAZ 15 A: Turn signal lights,
emergency flashers
24. ETCS 10 A: Multiport fuel injection
system/s equential multiport fuel injec-
tion system
25. EFI 20 A: Multiport fuel injection sys-
tem/sequential multiport fuel injection
system
26. DR/LCK 20 A: Power door lock system
27. TOWING 30 A: Towing converter
28. RADIO NO.2 20 A: Audio system
29. IGN 10 A: Multiport fuel injection sys-
tem/sequential multiport fuel injection
system, antilock brake system, trac-
tion control system (twowheel drive
models), active traction control system
(fourwheel drive models), vehicle sta-
bility control system, stop light, meter
and gauge
30. SRS 10 A: SRS airbag system
31. GAUGE 7.5 A: Meter and gauge
32. STA NO.2 7.5 A: Multiport fuel injec-
tion system/sequential multiport fuel in-
jection system

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
33. FR WIPWSH 30 A: Windshield wipers
and washer
34. 4WD 20 A: Fourwheel drive control
system
35. D P/SEAT 30 A: Driver ’s power seat
36. P P/SEAT 30 A: Front passenger ’s
power seat
37. PWR OUTLET 15 A: Power outlets
38. RR WSH 15 A: Rear window washer,
multiplex communication system
39. ECUIG 10 A: Shift lock control sys-
tem, power windows, antilock brake
system, traction control system (two
wheel drive models), active traction
control system (fourwheel drive mod-
els), vehicle stability control system,
electric moon roof, multiplex commu-
nication system, theft deterrent system,
rear height control air suspension 40. IG1 15 A:
Antilock brake system,
traction control system (twowheel
drive models), active traction control
system (fourw heel drive models), ve-
hicle stability control system, air c ondi-
tioning system, charging system, rear
window defogger, backup lights, turn
signal lights, emergency flashers, seat
heaters, AC inverter, instrument panel
light control, auto antiglare inside rear
view mirror, SRS airbag system
41. STA 7.5 A: No circuit
42. SECU/HORN 10 A: Theft deterrent sys-
tem
43. TAIL 10 A: Tail lights, license plate
lights, parking lights, instrument panel
light control, multiport fuel injection
system/s equential multiport fuel injec-
tion system, instrument panel lights,
meter and gauge, grove box light
44. ACC 7.5 A: Power outlets, outside rear
view mirrors, audio system, navigation
system, rear seat audio system, shift
lock control system, instrument panel
lights
45. CIG 10 A: No circuit Fuses (type B)
46. HEATER 50 A: Air conditioning system
47. AIRSUS 50 A: Rear height control air
suspension
48. AM1 50 A: All components in “ACC”,
“CIG”, “IG1”, “ECUIG”, “FR WIP
WSH”, “RR WIP”, “RRWSH”, “4WD”,
and “STA” fuses
49. TOWING BRK 30 A: Trailer brake con-
troller
50. J/B 50 A: All components in “PWR
OUTLET”, “D P/SEAT”, “P P/SEAT”,
“POWER”, “TAIL” and “SECU/HORN”
fuses
51. BATT CHG 30 A: Trailer sub battery
52. TOWING 40 A: Trailer lights (tail
lights)
53. ABS MTR 40 A: Antilock brake sys-
tem, traction control system (twowheel
drive models), active traction control
system (fourw heel drive models), ve-
hicle stability control system
54. AM2 30 A: Starter system, “IGN”,
“GAUGE”, “STA NO.2” and “SRS” fuses