Mercury Mountaineer (2002-2005) Fuse Diagram


Fuse box diagram (fuse layout), location, and assignment of fuses and relays Mercury Mountaineer (2002, 2003, 2004, 2005).

Mercury Mountaineer (2002-2005)

Checking and Replacing Fuses

Fuses and circuit breakers protect your vehicle’s electrical system from overloading. If electrical components in the vehicle are not working, the system may have been overloaded and blown a fuse or tripped a circuit breaker. Check the appropriate fuses before replacing any electrical components. A blown fuse can be identified by a break in the wire within the fuse.


  • Before replacing a fuse check that the key has been removed from the ignition and that all the services are switched off and/or disengaged.
  • Always disconnect the battery before servicing high current fuses.
  • Do not repair fuses and never replace a blown fuse with one that has a higher amp rating. This can severe wire damage and could start a fire.
  • Never replace a broken fuse with anything other than a new fuse.
  • Even after a fuse is replaced, it will continue to blow if the cause of the overload is not identified and corrected. If the fuse continues to blow, have the vehicle’s electrical system checked by your dealer or a qualified service technician.

Passenger Compartment Fuse Box

The fuse panel is located below the instrument panel on the driver’s side. To remove a fuse use the fuse puller tool provided on the fuse panel box.

Passenger Compartment Fuse Box Location

Passenger Compartment Fuse Box Diagram

ACircuits Protected
130Memory seat module, Driver power seat (2003-2005), Driver power lumbar (2005)
220Heated seats (2002), Moonroof
320Radio, Amplifier, Power antenna (2002), DVD
45Front wiper module
515Flasher relay (Turn, hazards)
610Right horn (2002), Key-in-chime (2003-2005)
715Heated mirrors
852004-2005: Heated PCV (4.0L engine only)
9-- (spare)
1010Heated backlight relay coil, Heated seat module (2002), Temp blend actuator (2002), A/C clutch contact
11202003-2005: Heated seats
1252002: Foglamp switch, 4x4 module
135Overdrive cancel switch, Flex fuel sender (2002-2003)
145PATS module
155Rear wiper module, Cluster, TPMS (2002-2003)
165Power mirror, Manual climate control, TPMS
1715Delayed acc. coil, Battery saver, Interior lamps (front and rear), Glove compartment lamp
1810Left horn (2002-2003), Flexible fuel pump (2004-2005)
1910RCM, PAD indicator (2002)
205Memory driver seat switch, Driver seat module, Body Security Module (BSM), PATS LED, Sunload sensor (2002-2003)
215Instrument cluster, Compass, Flasher coil
2210ABS, IVD Controller
23152002-2003: Brake pedal position switch, Driver brake applied relay, Redundant cruise deactivate switch
2415Cigar lighter, OBD II
255Mode-Temperature actuator for auxiliary climate control, Trailer tow battery charge coil, TPMS (2004-2005)
267.5Reverse park aid, Brake shift interlock, Approach lamp relay coil (2002), IVD switch
277.5Automatic dimming mirror, Digital transmission range sensor, Backup lamps
285Radio (Start)/DVD (Start)
2910Digital transmission range sensor, PWR feed to fuse #28 (Start feed)
305Daytime Running Lamps (DRL), Remote solenoid, DEATC climate controller, Manual climate control, Manual climate control temp blend actuator



The top side of the panel

These relays are located on the reverse side of the passenger compartment fuse panel. See your dealer or a certified technician for service of this relay box.

Passenger Compartment Fuse Box (Top Side)

Circuits Protected
2Rear defrost
3Delayed accessory
5Battery saver

Engine Compartment Fuse 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.

Engine Compartment Fuse Box Location

Engine Compartment Fuse Box Diagram



ACircuits Protected
430Rear defrost
540Anti-lock Brake System (ABS) pump
660Delayed accessory, Power windows (2004-2005), Audio (2004-2005)
720Power point #2
920Power point #1
1030ABS module (valves)
1140PTEC (2002-2003), Powertrain Control Module (PCM) (2004-2005)
1250Ignition relay/Starter relay
1340Trailer tow battery. Trailer tow turn signals
14102002-2003: Daytime Running Lamps (DRL) (Canada)
1515Memory (KAPWR) (2002), Memory (PCM/DEATC/Cluster) (2003-2005), Courtesy lamps (2003-2005)
1615Headlamp switch (2002-2003), Foglamp switch (2003), Park lamps (2004-2005), Autolamp parklamps (2004-2005), Front foglamps relay coil (2004-2005)
18204x4 (v-batt 1) (2002-2003), PCM with two-speed 4x4 clutch (2004-2005)
1920High beam relay
2030Trailer electric brake module
2130Front wiper motor
2220Autolamp; Low beam
2330Ignition switch, PCM diode (2004-2005)
25152004-2005: Brake on-off
26152002-2003: Fuel pump
202004-2005: Fuel pump
2720Trailer tow lamps, Trailer tow back-up
2820Horn relay
3020Rear wiper motor
3330Auxiliary blower motor
3430Power seats, Adjustable pedals
3520Rear power point (2002)
3640Blower motor
3715A/C clutch relay/Transmission
3815Coil on plug (2002-2003), HEGO (2004-2005), VMV (2004-2005), CMS (2004-2005), ESM (2004-2005), CVS (2004-2005)
3915Injectors/Fuel pump relay
4015PTEC power (2002-2003), PCM power (2004-2005)
4115HEGO (2002-2003), VMV (2002-2003), CMS (2002-2003), PTEC (2002-2003), Coil on plug (2004-2005; 4.6L engine only), Ignition coil (2004-2005; 4.0L engine only)
4210Right low beam
4310Left low beam
4415Front foglamps
455Brake pressure switch (2002)
2Brake pressure switch (ABS) (2003-2005)
4620High beams
6230Circuit Breaker: Delayed accessory (2002), Power windows (2003-2005)
48Fuel pump
49High beam
50Fog lamp
512002-2003: Daytime Running Lamps
52A/C clutch
53Trailer tow right turn
54Trailer tow left turn
55Blower motor
572002-2003: PTEC
2004-2005: PCM
592002-2003: Driver brake applied or Daytime Running Lamps
61A/C clutch

Rear Relay Box

The relay box is located on the rear passenger side quarter trim panel. See your dealer or a certified technician for service of this relay box.

Rear Relay Box

Circuits Protected
15Trailer tow back-up lamps
19Trailer tow park lamps
20Trailer tow battery charge
222002: Approach lamps