I need to know where is a nissan pathfinder amplifier location ?

Question edited for clarity.
Question moved to model category.

tail lights don't need relays as the amperage is very low. Only headlights and fog lights use relays.

https://www.google.com/search?q=1993+Nissan+Pathfinder.+Where+is+the+tail+light+relay

Fuse Box diagram

https://www.google.com/search?q=1993+nissan+pathfinder+fuse+box+diagram

..

There are three culprits that may cause this.

1:Many people have great luck with replacing the resistor unit for the blower motor. While I cannot guarantee this is the issue you have, it is the most common. (Approx $45. )
eBay link.. http://www.ebay.com/itm/Heater-Blower-Motor-Resistor-For-Nissan-Pathfinder-Xterra-Titan-Pickup-Truck-/131110853460?hash=item1e86d0db54&vxp=mtr

2: Others have luck when replacing the actual Plastic switch inside. This runs about $50

3: Then there is the blower motor amplifier.. (approx $110)
http://www.ebay.com/itm/NISSAN-PATHFINDER-BLOWER-MOTOR-AMPLIFIER-POWER-MODULE-1996-2004-/231422243697?pt=Motors_Car_Truck_Parts_Accessories&hash=item35e1d73371&vxp=mtr

Your service manual will show location of these items or a quick search online for schematic for your model will produce results to assist you from here.

Hope this helps.

Car Radio Battery Constant 12v+ Wire: Red/Black
Car Radio Accessory Switched 12v+ Wire: Blue
Car Radio Ground Wire: N/A
Car Radio Illumination Wire: Red/Yellow
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): Blue/White
Left Front Speaker Negative Wire (-): Blue/Yellow
Front Speaker Positive Wire (+): Brown
Front Speaker Negative Wire (-): Brown/White
Car Audio Rear Speakers Location: Side Panels
Left Rear Speaker Positive Wire (+): Red
Left Rear Speaker Negative Wire (-): Green
Right Rear Speaker Positive Wire (+): Blue
Right Rear Speaker Negative Wire (-): Pink

have a look at this

It is under the hood in the fuse box, refer to the owners manual for location in box.

Check this for...
-
2005 Nissan Pathfinder with Bose Audio Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Yellow
Car Radio Accessory Switched 12v+ Wire: Green/Black
Car Radio Ground Wire: Chassis
Car Radio Illumination Wire: Red
Car Stereo Dimmer Wire: Gray
Car Stereo Antenna Trigger Wire: Green
Car Stereo Amp Trigger Wire: Green
Car Stereo Amplifier Location: Under the Driver Seat
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): White
Left Front Speaker Negative Wire (-): Black
Right Front Speaker Positive Wire (+): Yellow
Right Front Speaker Negative Wire (-): Brown
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Black/Red
Right Rear Speaker Positive Wire (+): Blue
Right Rear Speaker Negative Wire (-): Black/White

-
2005 Nissan Pathfinder Car Radio Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Yellow
Car Radio Accessory Switched 12v+ Wire: Green/Black
Car Radio Ground Wire: Chassis
Car Radio Illumination Wire: Red
Car Stereo Dimmer Wire: Gray
Car Stereo Antenna Trigger Wire: Green
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Brown
Left Front Speaker Negative Wire (-): Blue
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Red
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Green
Left Rear Speaker Negative Wire (-): Black
Right Rear Speaker Positive Wire (+): Gray
Right Rear Speaker Negative Wire (-): Orange

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Should be a relay for the amplifier on the right fender.

replace all 3

Hi!!

The expansion valve is located in the High Pressure line very close to the evaporator, in the evaporator/blower housing under dashboard passanger side. To access it, need to remove evaporator.

Don't forget to rate this answer, Good Luck!!

dont know for sure but all nissans ive worked on are behind the passengers side kick panel ( passengers left foot )