Offroad Pics Video
 Articles & Info

 Project Jeep CJ-7
   

Reviews Great Products Tire Reviews Vendors

  Home Page
  Photo Album
  Tech Section
  Product Reviews
  Jeep Central
  Readers Rigs
  4x4 Club Links
  Links Directory
  4x4 Vendors
  Cool Products
  Shop for Junk
  Centralia PA
  Computer Help
  Contact
  Search
  Site Index
  Project CJ-7
  
Jeep Project CJ-7

An ongoing Budgeted Rebuild/Build up of a Rock Crawling Machine.

Jeep Central
From Jeep History to Tech Specs and Projects.  This section is all about Jeeps.
Jeep Technical Info
Engines
Transmissions
Transfercases
Axles
Engine Swaps

Installing 23,000 Volt Offroad Lights

What are HID Lights?

Onboard Air
Converting a York
AC Compressor
to Pump Air

Warn 9500i Winch Installation
 

HEI Ignition
Installation & Review

Lockers, Limited Slips &
other Differentials Explained


Jeep Dana 300 TeraLow - 4:1 Gearset for the Dana 300 Transfer Case

  


Smoke rises out of the ground, the smell of sulfur is in the air, the ground collapses as homes are destroyed.
Science fiction?
Think again.

 


2007 Jeep Wrangler JK
Jeep Wrangler JK Specs

h3-2.jpg (10058 bytes)
Hummer H3


Jeep Commander Articles and Reviews


Jeep Grand Cherokee Articles & Reviews


Nissan XTerra Articles and Reviews


Jeep Grand Cherokee Articles & Reviews


Jeep Rubicon Articles and Reviews


Jeep Rubicon Unlimited Articles and Reviews

Suspension Lift Installations and Reviews

 

 

 

 

Dept. Of Cheak Tricks

Automotive Wiring Tips - Using Relays

 

Things To Consider When Wiring Accessories...

When wiring anything in your vehicle that draws heavy current such as high powered offroad lights or audio amplifiers, there are a few things to consider.  Number one, make sure you use wire that is rated for the amperage that the accessories is going to pull.  It is always better to have wire that is OVER rated rather than wire that is not rated high enough.  If wire is used that is not rated to handle the current that your accessory will pull, the result could be overheated wires that could melt the insulation or the electrical plugs found throughout your vehicle (see image below), causing a short or worse yet it could result in a fire.  If you know how much current your accessory will draw you can determine what gauge wire is appropriate for your application.

 
Personally I like to use wire that far exceeds the current draw of my accessory.   It's overkill but in a few applications I've used heavy gauge stranded industrial wire with water and chemical resistant insulation. That way there is no question as to whether the wire is rated high enough or not.  If this approach is taken, it is very wise to place a fuse at the battery end as close to the battery as possible.  Most wire in a vehicle, if shorted out, will burn up before the battery overheats and possibly explodes.  If wire that is over-rated for vehicle use is used and a short occurs, a short will most likely result in damage to the vehicle of some sort unless a fuse is put in line as close to the battery as possible.  With the fuse there, in the case of a dead short, the fuse will burn out first before any damage could occur. 

 

Above, a melted electrical connector that had been overloaded.

T-Tap connector

Where to Get your Power

The second important thing to consider when adding accessories is to determine where you will get your power.  Many people will consider tapping into the hot wire of an existing circuit using something called a T-tap or quick slide connector, which are designed specifically for tapping into an existing wire.  This is not always a good idea for several reasons.  First and foremost, tapping into an existing circuit puts additional load on that circuit.  The additional load placed on a circuit or wire may exceed the limits of those wires, connectors and fuse.  Overloading a circuit will do one of two things.  First, it may blow a fuse.  So people will sometimes place a larger fuse in the fuse block to handle the extra load on that circuit.  BAD IDEA!  The fuse may hold but the resulting extra current may be more that the wire is rated for creating heat that can melt wires and connectors and start fires!  The connector to the right was overloaded and fused two adjacent terminals together, causing a short the blew the vehicles main fuse.  Before the fuse blew the connector actually started to burn.  The wire that carried the extra load also had melted its insulation and in places was exposed.  Luckily for the owner of this vehicle, it did not result in a fire but in many cases it does.

A better idea....

With accessories that pull a lot of power it is always better to get your power directly from the batteries positive terminal rather than tapping into the existing fuse block or wiring harness.  In most cases the vehicles existing fuse blocks, wires and connectors are not rated to handle the additional load of high powered accessories such as offroad lights and amplifiers.  If you are the kind of person that likes to add all kind of goodies to your vehicle it might be worth installing an additional fuse block that handles non-critical items like offroad lights, CB radios, power inverters, audio equipment, etc.  This additional block can then be powered by a heavy duty wire capable of carrying the current required of all the accessories on the block.  Be sure to fuse the block at the battery.

Another important thing to consider is how you control the switching on/off of the power to your accessories.  In almost every case where high current is required, the switch you will use to turn on the power should not handle the load because most switches are not designed to handle higher amps.  The job of switching the power is better left to a relay.   What is a relay?  A relay is a device that, through a magnetic induction coil, turns on the power for you.  The switch that is installed in the cab of your 4x4 actually only powers the relay itself which draws very little current.  In most  installations a 30 AMP relay from Radio Shack (Auto Relay Cat. Number 275-226) will do unless your amperage demands exceed 30 amps.  I like to used a lighted switch in the cab to let me know if driving lights are on.
 
 

Offroad Lights or Accessory Wiring Diagram using a 4 - Pole Relay Relay

Wiring Diagram using a 4 - Pole Relay Relay
Click to Enlarge

 

The method I use for wiring the lights and other external accessories, for the most part, follows the diagram pictured above.  As in the diagram a wire is run from a 12 volt power source to the switch in the cab and out to the relay placing a fuse at the source of the power.  (Follow the relay's wiring schematic when connecting the wires to the relay)  One of the relays terminals goes to ground.  Then run a heavy gauge wire from the battery to the relay placing a 30 Amp fuse in line very close to the battery.  Do not connect the power to the battery until all wiring is done.   Then I run a single heavy gauge wire out to the lights or other accessory. If installing lights, split it into two leads at the lights.  If you do this be sure the wire is rated to handle BOTH lights since it will carry the current of both.  The diagram shows two leads coming from the relay.  Then I run the second wire of the lights or other accessory to a good ground on the frame of the vehicle.  If the wires will not be soldered together and crimped connectors will be used it's a good idea to put a dielectric paste on the connectors where they come in contact.  This will prevent corrosion as time passes ensuring a good connection.   Then double-checked all wiring before plugging in the power. 

 

 

   
Ohms Law

Ohm's Law Defined

Ohm's Law defines the relationships between (P) power, (E) voltage, (I) current, and (R) resistance. One ohm is the resistance value through which one volt will maintain a current of one ampere.
( I ) Current is what flows on a wire or conductor. Current is measured in (A) amperes or amps.

( E ) Voltage is the difference in electrical potential between two points in a circuit. It's the push or pressure behind current flow through a circuit, and is measured in (V) volts.

( R ) Resistance determines how much current will flow through a component. Resistors are used to control voltage and current levels. The higher the resistance, the smaller the amount of current is allowed to flow. Resistance is measured in ohms.

( P ) Power is the amount of current times the voltage level at a given point measured in wattage or watts.

V = I x R
I = V / R
R = V / I
 

     

 

Alternative Offroad Lights or Accessory Wiring Diagram using a Relay
Wiring Diagram

      

Offroad Tire Info
P-Metric Tire Sizes Conversion to Inches
Tire Terminology
Wheel Terminology
How to Pick the Right
Tires for your Truck
Truck Tire Info
Tire Sizes Clearance Chart
Tires - What Hits What Fits
  
All Terrain  Mud Terrain
Tire Reviews & Info
Mud Terrain MT Tire Reviews
All Terrain AT Tire Reviews
Super Swamper Bogger
Super Swamper SSR
Super Swamper SX
Super Swamper Vortrac
Interco IROK TSL
Super Swamper LTB
Super Swamper TSL
Super Swamper TSL Radial
Super Swamper Narrow
Interco SS-M16 Swamper
Thornbird TSl Radial
Thornbird TSl Bias
Thornbird TSL
Parnelli Jone Dirt Grip
BFGoodrich Krawler
BFGoodrich MT T/A KM
BFGoodrich MT T/A KM2
BFGoodrich AT TA KO
BFGoodrich Mud King XT
Bridgestone Dueler MT
Cooper Discoverer ST
Cooper Discoverer STT
Cooper Discoverer ST/C
Federal Couragia MT
Firestone Destination AT
Firestone Destination MT
General Grabber MT
General Grabber AT2
Green Diamond Icelander
Ground Hawg Mud Tire
Hankook Dynapro MT
Hankook Dynamic MT RT01
Hercules Terra Trac MT
Hercules Trail Digger MT
Kelly-Springfield Safari DTR
Kelly-Springfield Safari MSR
Kumho Road Venture MT
Kumho Road Venture KL71
Kumho Road Venture AT
Dick Cepek Mud Country
Dick Cepek F-C II
Dick Cepek Fun Country II
Dick Cepek Fun Country Nylon
Dick Cepek Fun Country Kevlar
Mastercraft Courser MT
Mastercraft Courser HTR
Mastercraft Courser HTR Plus
Maxxis BigHorn Radial
Maxxis Creepy Crawler
Maxxis Trepador
Maxxis Buckshot Mudder
Maxxis MA-SW
Maxxis M-8080 Mudzilla
Maxxis MT-754 Buckshot
Maxxis MT-753 Bravo
Maxxis MA-751 Bravo
Maxxis MA-S2 Marauder II
Maxxis MA-S1 Marauder
Maxxis MT-762 BigHorn
Nitto Mud Grappler
Nitto Trail Grappler MT
Nitto Terra Grappler
Nitto Dura Grappler
Nitto Dune Grappler
Nokian Vatiiva MT
Pit Bull Rocker Extreme
Pit Bull Maddog
Pit Bull Growler
Goodyear Wrangler MT/R
Pro Comp Xterrain
Pro Comp All Terrain
Pro Comp Mud Terrain
Pro Comp Xtreme AT
Pro Comp Xtreme MT
Toyo Open Country AT
Toyo Open Country MT
TrXus Mud Terrain
TrXus STS All Terrain
Michelin LTX A/T²
Michelin LTX AT2 Press
Michelin LTX AT2
Mickey Thompson MTZ
Mickey Thompson MTX
Mickey Thompson Baja Claw Radial
Mickey Thompson Baja Claw Bias
Mickey Thompson Baja Crusher
Mickey Thompson Baja ATZ Radial SLT
Competition Claw
Dunlop Mud Rover
Federal Couragia M/T
Nitto Dura Grappler
Yokohama Geolandar
  
Dick Cepek's 2008 F-250 Super Duty Project Vehicle – Project CRUSHER
 
Mud Tire Reviews


Toyota
FJ Cruiser

Capacities
Dimensions
Engine Specs
Drivetrain Specs
Photo Gallery
FJ Cruiser Tires
Press Releases & Specs
FJ Cruiser Reviews


Paragon Adventure Park
Rock Krawl

Thousands more
photos here..»

 



Off-Road Lights
by LightForce Product Review / Installation.
from Off-Road Lights

 


Black Diamond Suspension Lift instal

 for CJ-7

Ramp Travel Index
RTI / Ramp Travel Index What it is and how to calculate it, with and without the ramp.

Offroaders Guide to Gearing up for Offroad
From Basic Equipment to Well Equipped.  An extensive list guide to help you prepare your vehicle for the offroad.

Do it Yourself
Detriot EZ Locker Install  in a 92 Toyota 8" rear


For all the Jeep
Fans out there!

Department of Cheap Tricks and Useful Tips
  
Ultra-Cool Hand Throttle for Free!

Jeep V8 Swap Tips

The Exploding Clutch

Radiator Protection using 6 bucks worth of material

Cracked Under Pressure - Fixing a smashed fingernail

A Cheap, effective alternative to undercoating

Home-built Saginaw Gearbox Brace for the cost of lunch!

Ammo Box Storage - Mounting Them for Quick Disconnect

Home-built Serious Skid-Plate protection for the Oil Pan for under 20 bucks!

  

Building a Garage?
Need a Garage Plan?
Need a House Plan?
 


Knoebels Amusement Park