2008 Mercury Grand Marquis Owner's Manuals

•The hazard lights control is
located on top of the steering
column.
•Depress hazard lights control to
activate all hazard flashers
simultaneously.
•Depress control again to turn the
flashers off.
FUEL PUMP SHUT-OFF SWITCH
FUEL
RESET
The fuel pump shut-off switch is a device intended to stop the electric
fuel pump when your vehicle has been involved in a substantial jolt.
After a collision, if the engine cranks but does not start, the fuel pump
shut-off switch may have been activated.
The fuel pump shut-off switch is
located on the left side of the trunk
behind the left rear tail light and the
trunk liner.
Use the following procedure to reset the fuel pump shut-off switch.
1. Turn the ignition to the OFF position.
2. Check the fuel system for leaks.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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3. If no fuel leak is apparent, reset the fuel pump shut-off switch by
pushing in on the reset button.
4. Turn the ignition to the ON position. Pause for a few seconds and
return the key to the OFF position.
5. Make a further check for leaks in the fuel system.
FUSES AND RELAYS
Fuses
If electrical components in the
vehicle are not working, a fuse may
have blown. Blown fuses are
identified by a broken wire within
the fuse. Check the appropriate
fuses before replacing any electrical
components.
Note:Always replace a fuse with one that has the specified amperage
rating. Using a fuse with a higher amperage rating can cause severe wire
damage and could start a fire.
Standard fuse amperage rating and color
COLOR
Fuse
ratingMini
fusesStandard
fusesMaxi
fusesCartridge
maxi
fusesFuse link
cartridge
2A Grey Grey — — —
3A Violet Violet — — —
4A Pink Pink — — —
5A Tan Tan — — —
7.5A Brown Brown — — —
10A Red Red — — —
15A Blue Blue — — —
20A Yellow Yellow Yellow Blue Blue
25A Natural Natural — — —
30A Green Green Green Pink Pink
40A — — Orange Green Green
15
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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COLOR
Fuse
ratingMini
fusesStandard
fusesMaxi
fusesCartridge
maxi
fusesFuse link
cartridge
50A — — Red Red Red
60A — — Blue Yellow Yellow
70A — — Tan — Brown
80A — — Natural Black Black
Passenger compartment fuse panel
The fuse panel is located below and to the left of the steering wheel by
the brake pedal. Remove the panel cover to access the fuses.
To remove a fuse use the fuse puller tool provided on the fuse panel
cover.
The fuses are coded as follows.
27 25
26 2423 21
2219
20
18 16
17 1514 12
1310
33
31
2932
30
28 11
97
8653
41
2Relay
1
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
1 10A Ignition (START) - Starter relay coil,
DTRS
2 7.5A Power mirrors, Door lock switches,
Mirror switch, Keypad switch, Decklid
switch, Adjustable pedal switch, DDM,
Cluster
3 5A Ignition (START) - Audio mute
4 10A LCM (switch illumination), Autolamp
sensor
5 7.5A Ignition (ON/ACC) - LCM
6 7.5A LCM
7 10A Ignition (ON/ACC) - Wiper module
8 10A Electronic Automatic Temperature
Control (EATC) module (vehicles
equipped with EATC only)
9 7.5A Ignition (ON/ACC) - Door lock switch
illumination, Heated seat switch
illumination, Moon roof, Overhead
console, Radio, Antenna,
Electrochromatic mirror, Window relay
coil
10 15A Hazards
11 15A Ignition (ON) - Turn signals
12 15A Audio
13 10A Ignition (ON) - Anti-lock Brake System
(ABS) module, Rear Air Suspension
Module (RASM), Variable Assist Power
Steering (VAPS), Cluster
14 15A Adjustable pedals
15 10A Ignition (ON) - EATC module, A/C mode
switch (vehicles equipped with manual
A/C only), A/C blower relay coil
16 20A Cigar lighter, OBD II
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
17 10A Ignition (ON) - A/C mode switch
(vehicles equipped with manual A/C),
Blend door, Heated seat modules, BTSI
(Floor-shift transmission)
18 15A Lighting control module (interior
lighting)
19 10A LCM (Left-hand low beam)
20 10A Ignition (ON/START) - Back-up lamps
21 10A LCM (Right-hand low beam)
22 10A Ignition (ON/START) - Restraint Control
Module (RCM), Occupant Classification
Sensor (OCS), Passenger Air bag
Deactivation Indicator (PADI)
23 15A Multi-function switch (Flash-to-pass),
LCM (High beams)
24 10A Ignition (ON/START) - Passive
Anti-Theft System (PATS) module,
Powertrain Control Module (PCM) relay
coil, Fuel relay coil, Ignition coil relay
coil
25 15A LCM (Park lamps, corner lamps, license
lamps)
26 10A Ignition (ON/START) - Cluster, LCM,
Overdrive cancel switch
27 — Not used
28 7.5A Brake signal, LCM (BTSI), ABS
29 — Not used
30 — Not used
31 5A Key in (LCM)
32 — Not used
33 — Not used
Relay 1 Full ISO relay Window relay
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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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 30A* Ignition switch
2 20A* Moon roof
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
3 10A* Powertrain Control Module (PCM) keep
alive power, Canister vent
4 20A* Fuel relay feed
5 10A* Rear Air Suspension Module (RASM),
VAPS
6 15A* Alternator regulator
7 30A* PCM relay feed
8 20A* Driver’s Door Module (DDM)
9 15A* Ignition coil relay feed
10 20A* Horn relay feed
11 15A* A/C clutch relay feed
12 20A* Audio (Subwoofer)
13 20A* Instrument panel power point
14 20A* Stop lamp switch
15 15A* Foglamps
16 20A* Heated seats
17 — Not used
18 — Not used
19 15A* Injectors
20 15A* PCM
21 15A* Powertrain loads and sensors
22 — Not used
23 — Not used
24 10A* Heated mirror, Rear defrost indicator
101 40A** Blower relay feed
102 50A** Cooling fan
103 50A** Instrument panel (I/P) fuse box feed #1
(I/P fuses 10, 12, 14, 16 and 18)
104 50A** Instrument panel (I/P) fuse box feed #2
(I/P fuses 2, 4, 6, 8, 19, 21, 23 and 25)
105 30A** Starter relay feed
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box Description
106 40A** Anti-lock Brake System (ABS) module
(Pump)
107 40A** Rear defroster relay feed
108 — Not used
109 20A** ABS module (Valves)
110 30A** Wiper module
111 — Not used
112 30A** Air suspension compressor
113 — Not used
114 — Not used
115 — Not used
116 — Not used
117 — Not used
118 — Not used
201
12ISO relay A/C clutch
202 — Not used
203
12ISO relay Ignition coil
204
12ISO relay PCM
205
12ISO relay Foglamps
206
12ISO relay Fuel
207 — Not used
208 — Not used
209
12ISO relay Horn
301 Full ISO relay Starter
302 Full ISO relay Air compressor
303 Full ISO relay Blower
304 Full ISO relay Rear defrost relay
501 Diode A/C clutch
502 Diode PCM
503 — Not used
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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