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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.
If the battery has been disconnected and reconnected, refer to the
Batterysection of theMaintenance and Specificationschapter.
The high-current fuses are coded as follows:
Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
1 Relay Blower motor/Variable blower
control (Dual Zone Climate Control)
2 Relay Electronic Shift-on-the-Fly (ESOF)
Lo-Hi
3 Relay Heater mirror
4 — Not used
5 30A* Trailer Brake Controller (TBC)
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
6 40A* ABS module (Pump)
7 30A* Upfitter auxiliary switch #1
8 30A* Upfitter auxiliary switch #2
9 40A* ABS module (Coil)
10 20A* Cigar lighter
11 20A* Instrument panel power point
12 15A** Brake On/Off (BOO) relay feed
13 5A ** Brake switch, Brake switch relay
coil, SJB module, 4x4 module
14 — Not used
15 — Not used
16 Relay A/C clutch
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
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
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
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
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
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
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
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
73 2A** Reverse Camera System (RCS)
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).Temporary spare tires are not
equipped with Tire Pressure Monitor System (TPMS) sensors if the
system is present.
The use of tire sealant may damage your Tire Pressure
Monitoring System (if equipped) and should not be used.
If your vehicle is equipped with a Tire Pressure Monitoring
System, refer toTire Pressure Monitoring Systemin theTires,
Wheels and Loadingchapter for more information. If the tire pressure
monitor sensor becomes damaged, it will no longer function.
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When driving with the temporary spare tiredo not:
•Exceed 50 mph (80 km/h)
•Load the vehicle beyond maximum vehicle load rating listed on the
Safety Compliance Label
•Tow a trailer
•
Use snow chains on the end of the vehicle with the temporary spare tire
•Use more than one temporary spare tire at a time
Use of a temporary spare tire at any one wheel location can lead to
impairment of the following:
•Handling, stability and braking performance
•Comfort and noise
•Ground clearance and parking at curbs
•Winter weather driving capability
•Wet weather driving capability
Stopping and securing the vehicle
To help prevent the vehicle from moving when you change a tire,
be sure the parking brake is set, then block (in both directions)
the wheel that is diagonally opposite to the tire being changed.
Refer to the instruction sheet (located in the glove box) for detailed tire
change instructions.
Park on a level surface, activate
hazard flashers and set the parking
brake.
•Automatic transmission: Place
gearshift lever in P (Park).
•Manual transmission: Place
gearshift lever in R (Reverse).
•Electronic Shift-On-the-Fly
(ESOF) 4x4: Place transfer case
in 4x4 HIGH or 4x4 LOW before
turning off the engine.
•Manual shift transfer case 4x4: Place transfer case in 4H or 4L.
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Location of the spare tire and tools
If your vehicle is equipped with a spare tire, jack and associated tools,
refer to the following table for their locations:
Tool Location
Spare tire (pick-up trucks only) Under the vehicle, just forward of
the rear bumper
Jack Regular cab and Crew Cab:
Fastened to floor pan behind
rearmost seat on passenger side
SuperCab: Under rear bench seat
on passenger side
Jack handle, lug wrench, lug
wrench extension (only available
on Dual Rear Wheel [DRW]
vehicles) and wheel chock (only
available on Single Rear Wheel
[SRW] vehicles equipped with a
diesel engine)Regular cab: Fastened to floor
behind driver seat
SuperCab: Fastened to floor under
rear seat
Crew Cab: Fastened to floor
behind rear seat at driver side
Key and spare tire lock In the glove box
Jack instruction sheet Under the jack tool kit
Removing the spare tire (with spare tire carrier only)
1. The following tools are required to remove the spare tire:
•one handle extension and two
typical extensions. To assemble,
align button with hole and slide
parts together. To disconnect,
depress button and pull apart.
•one wheel nut wrench. Slide over
square end of jack handle.
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•Vehicles equipped with dual
rear wheels,insert the lug
wrench extension into the lug
wrench to reach the lug nuts.
2. Attach the spare tire lock key (A)
to the jack handle (B).
3. Fully insert the jack handle (with
one extension) through the bumper
hole and into the guide tube. The
key and lock will engage with a
slight push and counterclockwise
turn. Some resistance will be felt
when turning the jack handle
assembly.
4. Turn the handle counterclockwise
and lower the spare tire until you
can slide the tire rearward and the
cable is slack.
5. Remove the retainer through the center of the wheel.
Tire change procedure
1. Turn engine off and block the
wheel that is diagonally opposite of
the flat tire using the wheel chock,
if equipped.If the vehicle is a
4x4,lock the manual hub on the
wheel.
2. Remove the jack, jack handle, lug wrench and spare tire from the
stowage locations.
3. Use the tip of the lug wrench to remove any wheel trim.
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