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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
35 10A Reverse Sensing System (RSS), 4x4
module, 4x4 solenoid, Traction control
switch, Tow/Haul switch (Diesel engine)
36 5A Passive Anti-Theft System (PATS)
transceiver, Cluster control
37 10A Dual automatic or Manual climate control,
PTC control
38 20A Subwoofer
39 20A Radio
40 20A 4x4 module, Satellite radio module
41 15A Radio, Electrochromatic rear view mirror,
Lock switch illumination
42 10A Heated seat relay coil, Upfitter switch
relay coils, Heated mirror relay coil
43 10A Fuel tank selector switch, 4x4 module
44 10A Run/Start customer access feed (PTO)
45 5A Front wiper logic, Blower motor relay coil
46 7.5A Not used (spare)
47 30A Circuit
BreakerPower windows, Moonroof, Power Sliding
Backlite
48 Relay Delayed accessory
Power distribution box
The power distribution box is located in the engine compartment. The
power distribution box contains high-current fuses that protect your
vehicle’s main electrical systems from overloads.
Always disconnect the battery before servicing high current
fuses.
To reduce risk of electrical shock, always replace the cover to
the Power Distribution Box before reconnecting the battery or
refilling fluid reservoirs.
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
17 Relay Not used
18 Relay Fuel Pump Driver Module (FPDM), Fuel
injectors (Gasoline engines), Diesel Fuel
Control Module (DFCM) (Diesel engine)
19 Relay Back-up lamps, Reverse Sensing System
(RSS), Engine compartment fuse 63
20 Relay Trailer stop/turn (Left)
21 Relay Trailer stop/turn (Right)
22 Relay Stop lamps, Center High-Mounted Stop
Lamp (CHMSL), TBC, Customer access
23 15A** Heater mirror
24 40A* Blower motor relay
25 — Not used
26 30A* ESOF relay lo-hi
27 50A* Glow Plug Control Module (GPCM) #1
(Diesel engine only)
28 20A* Heated mirror relay
29 30A* Passenger power seat
30 10A** A/C clutch relay
31 15A** Power fold mirror relay
32 20A** Fuel pump relay
33 20A** Back-up lamp relay
34 25A** Trailer stop/turn relay
35 5A** ESOF relay coils
36 10A**Gasoline engines:Powertrain Control
Module (PCM) keep alive power, Canister
vent
Diesel engine:Engine Control Module
(ECM) keep alive power
37 10A** Transmission Control Module (TCM)
(Diesel engine only)
38 — Not used
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
39 50A* ECM power (Diesel engine)
40 30A* Starter relay
41 20A* Power point (Center console - Front)
42 30A* Trailer park lamp relay
43 20A* Power point (Center console - Rear)
44 30A* Trailer battery charge relay
45 30A* Driver power seat or Memory module
46 40A* Run/Start relay
47 50A* GPCM #2 (Diesel engine only)
48 30A* ESOF relay hi-lo
49 30A* Wiper motor
50 30A* PCM relay coil, PCM relay (Gasoline
engines only)
51 — Not used
52 — Not used
53 Relay PCM power bus (Fuses 68, 70, 72, 74, 76)
(Diesel engine only)
54 Relay Starter solenoid
55 Relay Trailer tow park lamps
56 Relay Trailer tow battery charge
57 Relay Power Distribution Box (PDB) bus (fuses
67, 69, 71, 73, 75, 77)
SJB Run /Start bus (Fuses 29–37, 46)
58 Relay ESOF hi-lo
59 Relay PCM power bus (Fuses 68, 70, 72, 74, 76)
(Gasoline engines only)
60 Diode Starter relay (Gasoline engines only)
61 Diode A/C clutch
62 Diode Fuel pump
63 15A** Trailer tow back-up lamps
64 5A** Mirror marker lamps
65 — Not used
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
66 — Not used
67 — Not used
68 — Not used
69 — Not used
70 10A**Gasoline engines:A/C clutch relay coil,
Refrigerant Containment Switch, Heated
PCV
Diesel engine:A/C clutch relay coil,
Clutch switch, Fuel pump cooler, A/C
cycle pressure switch
71 5A** Fuel pump relay diode, PCM/ECM
Run/Start power
72 15A**Gasoline engines:Ignition coils
Diesel engine:Engine TCM
73 — Not used
74 20A**Gasoline engines:VPWR: HEGO, CMS,
MAFS, EVMV, CMCV, VCT, IMTV
Diesel engine:VPWR: Engine loads
75 5A** Back-up relay coil power
76 20A**Gasoline engines:VPWR: PCM
Diesel engine:VPWR: ECM
77 10A** ABS module logic
* Cartridge fuses ** Mini fuses
CHANGING A FLAT TIRE
If you get a flat tire while driving:
•do not brake heavily.
•gradually decrease the vehicle’s speed.
•hold the steering wheel firmly.
•slowly move to a safe place on the side of the road.
Your vehicle may be equipped with a conventional spare tire that is
different in one or more of the following: type, brand, size, speed rating
and tread design. If this is the case, this dissimilar spare tire is still rated
for your vehicle loads (GAWR and GVWR).
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IDENTIFYING COMPONENTS IN THE ENGINE COMPARTMENT
Refer to the6.0/6.4 Liter Power Stroke Direct Injection Turbo Diesel
Owner’s Guide Supplementfor diesel engine component locations.
5.4L V8 gasoline engines
1. Windshield washer fluid reservoir
2. Battery
3. Transmission fluid dipstick (automatic transmission)
4. Engine oil filler cap
5. Engine oil dipstick
6. Power steering fluid reservoir
7. Brake fluid reservoir
8. Engine coolant reservoir
9. Air filter assembly
10. Power distribution box
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6.8L V10 gasoline engine
1. Windshield washer fluid reservoir
2. Battery
3. Transmission fluid dipstick (automatic transmission)
4. Engine oil filler cap
5. Engine oil dipstick
6. Power steering fluid reservoir
7. Brake fluid reservoir
8. Engine coolant reservoir
9. Air filter assembly
10. Power distribution box
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4. Poor wiper quality can be improved by cleaning the wiper blades and
the windshield; refer toWindows and wiper bladesin theCleaning
chapter.
5. To prolong the life of the wiper blades, it is highly recommended to
scrape off the ice on the windshield before turning on the wipers. The
layer of ice has many sharp edges and can damage the micro edge of the
wiper rubber element.
ENGINE OIL
Checking the engine oil
Refer to thescheduled maintenance informationfor the appropriate
intervals for checking the engine oil.
1. Make sure the vehicle is on level ground.
2. Turn the engine off and wait a few minutes for the oil to drain into the
oil pan.
3. Set the parking brake and ensure the gearshift is securely latched in P
(Park) (automatic transmission) or 1 (First) (manual transmission).
4. Open the hood. Protect yourself from engine heat.
5. Locate and carefully remove the engine oil level indicator (dipstick).
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•5.4L/6.8L engine
6. Wipe the indicator clean. Insert the indicator fully, then remove it
again.
•If the oil level isbetween the MIN and MAX marks,the oil level is
acceptable.DO NOT ADD OIL.
•If the oil level is below the MIN
mark, add enough oil to raise the
level within the MIN-MAX range.
•Oil levels above the MAX mark may cause engine damage. Some oil
must be removed from the engine by a service technician.
7. Put the indicator back in and ensure it is fully seated.
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