Engine/Transmission (1994 - 1998) Headlight gremlin

[Stmpplr]

I seem to have developed self dimming headlights. When first turned on they operate correctly. Usually within a couple of minutes they will fade out and then fade back on a couple of times. May stay dimm for 5-10 secs. They fade in and out, not on and off like like using the switch. Won't do it all the time of course. There is no change in any other lights when this happens, not outside or dash. No change in reading on volt meter,(app 14V. ) Is there a relay just for the headlights that may be going bad? I can't think of anything else that would cause this behavior, (other than it being Dodge Parts,).

Hope some one has some ideas. Thanks.

Jim

 

[Nyoest]

Do you still have your original headlight switch? They were prone to failure/melting and can cause this problem.

 

[Stmpplr]

I am on the second light switch, replaced with the oem unit so I guess it could be going out. Is there an alternative replacement, or maybe wire to a relay?

 

[hsmith]

Mine was done under warranty, a long time ago obviously. New switch, harness, including adding a relay. No problems since. That was probably in '97.

 

[Nyoest]

A switch from napa comes with new connector and 6 inches of new leads. The swithch gets hot and let's the truck side plastic connector melt.

 

[HCannon]

If you pull a trailer and have trailer lights that speed the melt downs up. I put my trailer on a switch of its own. I lost three switches before I did this. Havent lost one now in a good while. Mine would act like you say yours is doing now before they would go out.

 

[Stmpplr]

Looks like it's the headlight switch from all the replys. Next question is the solution.

I have a relay block I was going to install to add some driving and fog lights so I guess I could wire the headlights to it too. It has 4 or 5 circuits. Anyone know of any potential problems going this route?

Thanks for the replys.

 

[HCannon]

Genos has what they call a brite box that might do what you wont to do. I thank it may have a relay that supplies the power to your lights without putting the load on your switch. Over a 100 dollars, it should have a relay.

 

[Stmpplr]

Can I use the switch wiring to trigger 2 relays, one for high beams and one for low? This would seem to requre only splicing the relays into the existing wiring and feeding them power off the battery.

Will this work?

 

[fest3er]

Can I use the switch wiring to trigger 2 relays, one for high beams and one for low? This would seem to requre only splicing the relays into the existing wiring and feeding them power off the battery.

Will this work?

Yes, that will work.

1. Prepare two standard relays (same as the larger ones in the PDC under the hood).
   
2. Connect B+ to one 'switch' pin of each relay.
   
3. Connect a good ground to the ground pins of each relay control.
   
4. Find the two 'hot' wires that go to the headlights (low and high beam).
   
5. Cut them.
   
6. Connect the low beam lead from the cab to one relay's other 'switch' pin.
   
7. Connect its mate to the control input pin of the relay.
   
8. Connect the high beam lead from the cab to the other relay's 'switch' pin.
   
9. Connect that lead's mate to the control input pin of the other relay.
   

Use standard crimp spade/lug connectors. You might solder the high-current connections as well as crimping them.



If you're clever, you can use spare relay sockets in the PDC for the relays.



The trailer tow relay handles the running lights for the trailer.



Done right, your headlights will be powered through the relays and your inside switches will pass low current to control the relays (and the full current for the running lights).



If you want to remove all high-current from the switch, you can wire in a third relay to handle the running lights. Then the dash switch will pass only (relatively) low current.



Alternatively, you could wire the relays under the dash *after* the multi-function switch. But since everything you need to access is right in the PDC, I'd say that's the best place to put the relays.

 

[RMcKinney]

Stmpplr,

Mine was the same.

Dodge had a recall for the dash light switch so you might get them to install one for nothing.

I exchanged mine with one from napa and it worked better that the old one but you really need to check out a relay harness like an Auto Direct 9007 Harness Relay.

$39. 00 last time I looked and just plugs into the existing harness.

When I did this my dims are brighter that my brights.

My is about 8-9 years old with No problems.

RMcKinney 1995 2500 stock with 270,000 miles

 

[SRath]

You need to find a permanent solution. There have been instances of these trucks actually burning to the ground from that headlight switch meltdown problem. There are lots of different methods, homebrewed & commercial, but it all comes down to installing separate relays in the end.



As mentioned already, if you ever tow at all, even just a little two-taillight trailer, don't forget to put relays on the rear lights, too. I ran a heavy 6 gauge wire from my + battery terminal back to a waterproof junction box for a semi trailer and put separate relays on the rear lights and trailer connector, and added an electric brake controller and battery isolator circuit and bright tractor utility lights for backup lights while I was at it. The factory wiring carries only the miniscule amount of juice to operate the relays now.



My headlights were trickier since I have the added burden of a badly-designed Boss snowplow wiring harness that reroutes all the headlight juice all the way back to a toggle on the dash then back to the headlights to enable me to select between truck headlights or snowplow headlights. The added wiring just exacerbated the overloaded and overheated problems. There were no aftermarket solutions available.



So David (dresslered here on TDR) whipped up an extremely elegant (meaning simple & effective) relay wiring schematic just for my situation. He's an engineer and electrical genius. And a genuine nice guy. If you have questions or problems, you might look him up. I've always thought/hoped he could post a do-it-yourself relay wiring schematic that would solve the problem for do-it-yourselfers that should be a permanent sticky here. (on the 2nd gen non-engine/transmission forum). He's a busy guy and just became an AARP junkmail recipient (sorry David old man, but you are two days older than me), so I probably shouldn't be "volunteering" him, but he does great work.



The issue then becomes finding quality components to use; and not all relays, relay sockets, headlight sockets, wiring, etc are created equal. In fact, much of it is very low-quality foreign made junk. There is one company I found (in Ohio if i recall) that does make & supply top-notch components. I'll have to see if I can find them again. All of their info was on my old laptop that burned up... (HP must use the same electrical engineers that mopar does).

 

[GAmes]

I did much like fest3er, but with one additional step. I installed a diode between the high and low beam leads so that the low beams get power when the high beams are on.



This article might help.



Ram headlight switching modifications