Nissan Repair: Instrument panel lights and electrical problems, speedomter, high beams

Question
QUESTION: OK briefly what happened, someone tried to install a radio, right after headlights, interior lights, instrument panel lights, everything went phooey including odometer and speedometer!  i disconnected radio and took out! but only got tailights and turn signals now along with only high beams working on headlights but only one low beam works, my biggest problem now is i need to know where can i find the BIG ENCHILADA OF A FUSE OR FUSES to either replace or repair that could get the instrument panel and odometer and speedomter working again? i heard it was under the hood.. if it is i have no clue what i'm looking for..it is not in a chilton's manual or anywhere else as far as info on nissan...any help would be appreciated!! thanks!

ANSWER: Gail,

YEs, Nissan uses a floating ground on the radio circuit and if wired wrong the power will backfeed.  The large master fuse is on the positive post of the battery.  But, if the instrument fuse should be blown and be the problem for that.  The headlights use seperate fuses for left and right along with seperate relays.  I would check those too.  Now, if all the fuses check good then you are looking at the step transformer for the cluster and possibly the headlight switch if the fuses and relays are good.  Here are the wiring codes for the car.  Make sure the connector that was cut and the wires are not touching.
12volts white/blue + ignition harness
Starter white/red + ignition harness
Second Starter white/green + ignition harness
Ignition black/red + ignition harness
Accessory white/black + ignition harness
Keysense black/red + ignition harness
Power Lock red - driver door module in door
Power Unlock lt. blue (double pulse) - driver door module in door
Lock Motor purple 5wi white plug, pin 30 at BCM
Unlock Motor yellow 5wi white plug, pin 23 at BCM
Disarm Defeat white/red 5wi white plug, pin 31 at BCM
Parking Lights+ red/blue + driver kick panel
Hazards green/red - brown plug, pin 61 at BCM
Turn Signal(L) green/white + white plug, pin 22 at BCM
Turn Signal(R) purple/white + white plug, pin 21 at BCM
Reverse Light lt. green + driver kick panel
Door Trigger white (L), pink (R) - white plug, pin 14, 10 at BCM
Dome Supervision comes on with unlock
Trunk/Hatch Pin red/white - white plug, pin 18 at BCM
Hood Pin lt. green/black - hood pin switch under hood
Trunk/Hatch Release pink - brown plug, pin 76 at BCM
Factory Alarm Arm arms with lock
Factory Alarm Disarm disarms with unlock
Disarm No Unlock single pulse power unlock wire
Tachometer NOT white/blue or black ac any ignition coil
Brake Wire pink/blue + brake pedal switch
Parking Brake purple - parking brake switch
Horn Trigger green/black - steering column


navi:
Speed Sense white 8P Unified Meter and A/C Amp, pin 26
The Unified Meter and A/C Amp is behind the A/C controls in the center console.

audio:

Radio 12v
yellow
+
radio harness


Radio Ground (chassis)
Radio Ignition lt. green + radio harness
Radio Illumination red/blue + radio harness
Factory Amp Turn-on green/yellow + radio harness
Power Antenna green/white + radio harness
LF Speaker +/- blue/red - black/white +,- radio harness
RF Speaker +/- yellow/red - red/white +,- radio harness
LR Speaker +/- lt. green/red - black/yellow +,- radio harness
RR Speaker +/- blue/orange - black/pink +,- radio harness



---------- FOLLOW-UP ----------

QUESTION: thanks for the info already that you have gieven although i need to ask something in relation to  it...i don't know if this helps as far as wiring schematics...because there is absolutely no radio no nothing in the truck anymore that space is completely empty..when everything went out..it scared me so bad i took it out and just put electrical tape around the end of the wires that was hooked to the radio...now i taped the ends of the wires all individually and nnone of them are touching each other at all...was there a wire or wires that i was suppose to put back together touching each other even though there is no radio whatsoever now?,,,i wasn't the one who installed it and made it go phooey..all i did was disconnect everything so any info on this would be great!   thanks again for your time..awesome info so far!

Answer
Gail,

If there was an amplifier in the trunk as part of the radio it was probably not grounded properly and the bulbs are blown.  I once worked on a Toyota where every bulb in the vehicle was blown from an aftermarket amplifier not being grounded.  The voltage backfed through the car and burnt out many things.  Try switching the bulbs from side to side to see if they are blown.  Also, make sure you check every fuse before you start replacement of switches and such.