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Bulb Replacement
For the proper type of replacement
bulbs, or any bulb changing procedure
not listed in this section, contact your
dealer.
Caution
Do not replace incandescent bulbs
with aftermarket LED replacement
bulbs. This can cause damage to
the vehicle electrical system.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.
Front Turn Signal Lamps
Uplevel
See your dealer for turn signal
replacement.
Base level
To replace one of these lamps:1. Turn steering wheel in opposite
direction as the bulb in need of
replacing.
2. Remove fasteners retaining the front wheel liner.
3. Pull back wheel liner to expose back of turn signal lamp.
4. Remove turn signal bulb socketfrom lamp housing by rotating
counterclockwise.
5. Replace the bulb and reverse Steps 1–4 to reinstall.
Back-Up Lamps
To replace one of these bulbs:
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1. Remove the fasteners to removethe trailer hitch cover.
2. Access the lamp through the opening in the underbody.
3. Disconnect the electrical connector from the bulb
assembly.
4. Turn the bulb socket
counterclockwise and pull the
bulb straight out of the socket.
5. Replace the bulb and reverse Steps 1–4 to reinstall.
Electrical System
Electrical System Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the current electrical load is too
heavy, the circuit breaker opens and
closes, protecting the circuit until the
current load returns to normal or the
problem is fixed. This greatly reduces
the chance of circuit overload and fire
caused by electrical problems.
Fuses and circuit breakers protect
power devices in the vehicle.
Replace a bad fuse with a new one of
the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, the
same amperage fuse can be borrowed.
Choose some feature of the vehicle
that is not needed to use and replace
it as soon as possible.
Headlamp Wiring
An electrical overload may cause the
lamps to go on and off, or in some
cases to remain off. Have the
headlamp wiring checked right away if
the lamps go on and off or remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected from
electrical overload, overload due to
heavy snow or ice may cause wiper
linkage damage. Always clear ice and
heavy snow from the windshield
before using the windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
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breakers. This greatly reduces the
chance of damage caused by electrical
problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the
specified amperage rating when
replacing fuses and circuit breakers.
Use of an oversized fuse or circuit
breaker can result in a vehicle fire.
You and others could be seriously
injured or killed.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace a
bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another
fuse location, if a fuse goes out.
Replace the fuse as soon as possible.
Engine Compartment Fuse
Block
The underhood fuse block is in the
engine compartment, on the driver
side of the vehicle.
Caution
Do not pull the engine
compartment fuse block lever, since
it is intended only for service
purposes. If pulled, vehicle
malfunction may occur.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.
To remove the fuse block cover, press
the clips on the cover and lift it
straight up.
The vehicle may not be equipped with
all of the fuses, relays, and features
shown.
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FusesUsage
3 Antilock brake system pump Fuses
Usage
5 Trailer brake
6 Rear closure Fuses
Usage
7 Trailer stop/Turn LH
8 Memory seat module
9 Pedestrian friendly alert function
10 Semi-active damping system
11 DC DC Battery 1/2
12 Rear defogger
13 Heated mirror
14 –
15 Passive entry passive start
16 Front wiper
17 Passenger power seat
18 Power liftgate module
19 Driver power seat
21 Sunroof
22 Rear wiper
23 Trailer interface module 2
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FusesUsage
26 Transmission control module/Ignition
27 Instrument panel body/Ignition
28 Rear wiper
29 Trailer ignition
30 Malfunction indicator lamp
32 Rear drive control module 1
33 Front heated seat
34 Handsfree/Window switch
35 Diesel exhaust fuel heater
36 Fuel module
39 Massage
40 Steering column lock
41 –
43 Heated steering wheel
44 Seat ventilation Fuses
Usage
46 Engine control module/Ignition
48 Rear drive control module 2
49 Heating ventilation/ Air conditioning
blower motor
50 –
51 –
54 –
55 –
56 Starter motor
57 –
58 –
59 High-beam headlamps left/right
60 Trailer interface module 1
61 –
62 –
63 – Fuses
Usage
65 Air conditioning control
67 –
68 –
69 –
70 Trailer park lamp
72 Starter pinion
75 Engine control module
76 Powertrain off engine
78 Horn
79 Washer pump
81 Transmission control module/Engine
control module/
Cooling pump
82 Nitrogen oxide sensor
83 Ignition coil
84 Powertrain on engine
85 Shunt
86 Shunt
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FusesUsage
87 Diesel fuel heater 1
88 Aeroshutter
89 Selective catalytic reduction module
92 Trailer stop/Turn right
93 Automatic headlamp leveling/Canister vent
solenoid
95 Smart sensors
96 Diesel fuel heater 2
99 –
Relays Usage
4 –
20 Rear defogger
25 Front wiper control
31 Run/Crank
37 Front wiper speed
42 –
64 Starter motor Relays
Usage
66 Powertrain
71 Trailer park lamp
73 Air conditioning control
80 Starter pinion
90 Powertrain sensor
94 Diesel exhaust fuel heater
98 Diesel fuel heaterInstrument Panel Fuse
Block
The instrument panel fuse block is on
the driver side of the instrument
panel, between the steering wheel and
the door. To access the fuses, remove
the panel, starting at the top. Once
clips are disengaged, the tabs along
the bottom of the door can be
disengaged from the instrument panel
to remove the door.
To reinstall the door, place the bottom
tabs into the slots, and rotate the door
into position, engaging the clips.
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The vehicle may not be equipped with
all of the fuses, relays, and features
shown.
FusesUsage
F1 Left power window
F2 Right power window
F3 –
F4 DC DC battery 2/1
F5 Auxiliary power outlet–cargo Fuses
Usage
F6 Heated seat battery 1
F7 Heated seat battery 2
F8 Body control module 3
F9 Electric parking brake switch
F10 Body control module 2 (Stop/Start)
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FusesUsage
F11 –
F12 –
F13 –
F14 –
F15 Transmission control module (Stop/Start)
F16 Amplifier
F17 –
F18 Video processing module
F19 Power steering column
F20 Body control module 6
F21 Body control module 4
F22 Body control module 7
F23 Electric steering column lock
F24 Airbag
F25 Data link connector
F26 –
F27 –
F28 – Fuses
Usage
F29 Body control module 8
F30 Overhead console
F31 Steering wheel control
F32 –
F33 Heating ventilation/Air conditioning
F34 CGM
F35 Heated switch
F36 Charger
F37 Auxiliary power outlet–front
F38 OnStar
F39 Display
F40 Obstacle detection
F41 Body control module 1 (Stop/Start)
F42 Radio
F43 Auxiliary power outlet–console (circuit
breaker)
F44 Auxiliary power outlet–console Relay
Usage
K1 –
K2 Retained accessory
power
K3 –
K4 –
K5 –