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Circuit Breaker Usage
1 Stoplamps
2 Center High Mounted Stop Lamps
3 Parking Lamps
4 Powertrain Control Module
5 Auxiliary Wiring
6 Heater/Air Conditioning
7 Hazard Warning FlashersCircuit Breaker Usage
8 Power Post
9 Courtesy Lamps
10Warning Lights, Gages and
Indicators
11 Crank
12 Rear Axle
13Trailer Turn Signals/Hazard Warning
Flashers
14 Radio/Chime
15 Daytime Running Lamps
16 Air Bag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Chassis
A Spare
B Spare Fuse Block 2
5-90
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Underhood Fuse Block
When a circuit goes out, the problem could be in either
the primary or secondary underhood fuse blocks.
These blocks uses blade-type fuses.
Both underhood fuse
blocks are located in the
engine compartment,
on the passenger’s side of
the vehicle.
To access the fuse blocks, gently squeeze both sides of
the cover to unlatch the tabs at the top. Then, unsnap
both attachments at the bottom and remove the cover.
Be sure to replace fuses with fuses of the same
rating. Do not use fuses of higher amperage than those
indicated on the fuse block.Relay Usage
NOTE 1 LG4 Powertrain Control Valve,
L18/LB7 Fuel Pump, LG5 Heated
Fuel
IGN B Ignition
STARTER Starter
HORN Horn
IGN A Ignition Primary Underhood
Fuse Block
Primary Underhood Fuse Block
5-91
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Fuse Usage
IGN 1 Ignition 1
IGN 4 Ignition 4
IGN 3 Ignition 3
BATT/HAZ Battery/Hazard Warning Flashers
HEADLAMP Headlamps
LIGHTING Interior/Exterior Lamps
HVAC Comfort Control System
NOTE C4/C5 Electric Brake,
C6/C7/C8 Brake Lamps
Capacities and Speci cations
Capacities and Speci cations
Engine RPO
7.2L L6 HEUI Fuel System LG5
8.1L V8 SPFI Fuel System L18
7.8L L6 Common Rail Fuel System LG4
6.6L V8 Common Rail Fuel System LB7/LLY Secondary Underhood
Fuse Block
5-93
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I
If No Steam Is Coming From Your Engine..........5-37
If Steam Is Coming From Your Engine...............5-36
If You Are Caught in a Blizzard.........................4-27
If You Are Stuck in Sand, Mud, Ice or Snow.......4-29
If Your Diesel Engine Won’t Start......................2-20
Ignition Positions.............................................2-12
Illuminated Entry.............................................3-16
Infants and Young Children, Restraints...............1-29
Inflation - Tire Pressure...................................5-68
Instrument Panel
Cluster.......................................................3-24
Overview..................................................... 3-4
Switchbank.................................................3-16
Instrument Panel Brightness Control..................3-15
Instrument Panel Fuse Block............................5-88
Inter-Axle Differential Lock Control.....................4-10
Interior Lamps................................................3-15
J
Jump Starting.................................................5-56
K
Key Lock Cylinders Service..............................6-28
Keyless Entry System....................................... 2-3
Keys............................................................... 2-2
L
Lamps
Exterior......................................................3-13
Interior.......................................................3-15
Lamps Check.................................................6-27
Lap Belt........................................................1-22
Lap-Shoulder Belt...........................................1-13
Light
Air Bag Off .................................................3-28
Air Bag Readiness.......................................3-27
Anti-Lock Brake System Warning...................3-34
Brake System Warning.................................3-31
Change Engine Oil......................................3-39
Charging System.........................................3-30
Check Gages Warning.................................3-42
Daytime Running Lamps Indicator..................3-41
8