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Ram Headlight & Fog Light Mods

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Subject:      Hi Beams FIXed
From:          Scott Bessel <>

Here is the procedure on the headlight fix I did to my '96 Indy RAM - it will allow both High and Low beams to be on the same time, just like the passing switch.  Please let me know how it works for you.

Good Luck,   Scott

NOTE: The schematic below works with a fixed font. If your browser is set to override the font, the diagram may not work. Dave

Parking Lights>--------- BLACK/YELLOW -----o
    High Beam>---------- RED/ORANGE ------ )----o
                                           |    |
                                           |    |
                    RELAY                  |    |
                                           |    |
 Low Beam>-----o----> / <----o ------------o    |
(VIOLET/WHITE)       /                          |
               o---->                           |
           o---o----mmmmm----o -----------------o
           \ Chassis Ground

** Switch this message to Courier non-true-type font to read **

This has been tested on my 1996 Dodge RAM and all is correct according to the manual.  I am not sure if the wire color codes have changed over the years.  To verify check the back of the headlamps and parking lamps.

I purchased a standard 30A 12-volt relay from my local Auto Parts store, these are fog light style.  You will also need Wire tabs, Blue clips that allow you to splice one wire on to another without breaking the connection.

The relay should be labeled on the side with a picture like mine above. the mmmmm is the coil lines.

Find a suitable mounting location for the relay, I placed mine just under the batter on the drivers side, connect one side of the coil to ground, try the screw you just mounted the relay with.

You will need to locate the Lamp wires for the next steps, I found mine in a wire loom coming out from under the battery going under the radiator.  Split this loom open and expose the wires, you should find all of the above colors and more.

You will need to tap into the RED wire with the ORANGE stripe, this is the high beam line, Using the blue tap and a spade lug connect it to the other side of the relay coil wire.

Now if you turn on your high beams you should be able to hear the relay slick on and off.  At this point smoke is bad...

Now tap into the Low Beam line, VIOLET wire with the WHITE strip, connect the wire you tapped into this lead to the relay line that is not normally selected, I.E. normally open, not connected when the relay is off.  (Do not worry too much as if wrong you can easily switch later)

Now last, tap into the BLACK wire with the YELLOW stripe, connect that to the common switch lead on the relay.

Time to test.  Headlamps on hit the passing switch, both filaments should light, click into full high beams and both should stay on.  Turn high beams off and all should reset to low beams.  If this does not work then recheck your wiring, it is possible you crossed the low beam line.

****  I am not any way guaranteeing this procedure, I am just saying that I have done it on my '96 RAM and it works.  I will take no responsibility if you blow your truck up.  (Don't worry all the lines you are working on are fused and protected)

2000 models:

12 volts is always present at the lamp socket;  the headlamp switch is completing the circuit by providing a path to ground—useful if you want to trigger relays using the wires at the lamp socket.

2000 non-sport wire colors:
VT (left) VT/RD (right) 12 volts
VT/WT (left & right) low beam RD/OR (left & right) high beam

I have not tried this modification personally. Some say that the bulbs will burn out or the headlight lenses will melt. Several people have reported no problem with running both beams. I know someone who drove his Ram the entire length of the Alaska highway with no problem while holding the light switch in "hi beam flash" position to keep both beams running. As Always, YMMV!    Dave

Another alternative is the ZETA headlamp module which runs only one filament, but boosts the voltage delivered to the filament to brighten the light. Installation informtation on WWCD2's web page. WWCD2's TDR Group purchase deal.

Fog Lamp enable with high beams

The fog lamps are wired so that when the high beams are on, the fog lamps are off. Some like to run the fogs with high beams because they help fill the road near the truck, and the wide beam helps the driver to see animals and debris at the side of the road. Various relay interlocks have been used through the Ram model years. Here are interlock defeats for some model years.

1996 and 1997 Models

From  Scott Bessel and Ryan Ross:
      In the engine compartment, next to the battery, remove "FOG LAMP RELAY #1" cut off pin 2 on this relay, reinsert and poof you are ready to go.

1998 Models

from "Michael Lang" <>
      Remove Fog Relay #2, cut off pin #2, then reinsert the relay.

from  "Paul M. Anton" <>
      Two relays are used to control the fog lamps. The first relay actually turns the lights on and off. The second is the High Beam interlock relay. This relay is normally off and provides a path for the fog lights through its normally closed contacts.
      Remove this relay and replace the normally closed contacts with a jumper. This can be made up with a couple of crimp on spade connectors and a short jumper wire. One of the spade connectors will have to be trimmed, since one of the slots in the relay socket is narrower than the other.
     As I sit here in front of the computer, I seem to remember that the relay locations are marked on the cover of the fuse & relay block under the hood. I further think that there is a diagram of the pinouts on the relay itself.

1999 Models

Remove the fog lamp relay and install a jumper between pins #3 and #5. (TDR Forum)
More from Thad A. McCall:    I did the mod, jumping pins 3 and 5 and it worked great. After making sure it worked, I took my relay apart and gutted it, then jumped 3 and 5 and put the cover back on the relay, gives it a nice clean appearance.

2000 and 2001 Models

      A single fog lamp relay is interlocked to the high beam filiment. To permit fog light operation with high and low beams, remove the fog relay and install a jumper, with a 1/4" spade lug on each end, between the two large terminals.


      Relay Socket

         |              |
         |   |   |   |   |

         |    ___    |   _______

         |              |                 |

         |              |                                       Jumper
         |    ___    |   _______|

In the right front of the PDC is the Fog lamp relay. Install the jumper between the two large terminals ( #87 & #30) that are parallel to the relay ends.
The Fog Relay is a rectangular relay located at the front left corner (left=driver side) of the Power Distribution Center under the hood. Pull the relay and insert a short jumper (long jumper is for test and photo purposes).



Last update May 3, 2001