bad headlight switch

[red98rover]

Just replaced my 3rd headlight switch on my 1998.5 ram 3500 with 278k miles. I now tow a 25ft 5th wheel.
Any suggestions?

 

[BigPapa]

I’d say you’re not running a relay harness for your headlights. That would be the single biggest thing to help alleviate your issue. You can build your own or buy one at LMC Truck.

 

[mtarcher1]

Just replaced my 3rd headlight switch on my 1998.5 ram 3500 with 278k miles. I now tow a 25ft 5th wheel.
Any suggestions?

As noted, a relay is the best fix. Meanwhile, don't use the dashlight dimmer function on the switch since that seems to cause excess heat in the switch.

 

[Wiredawg]

Installing a relay is a good fix.

There was another fix old 2nd Genners may remember. I can't remember what I drilled, maybe 1/2 hole bottom of A/C vent tube for extra cooling, and possibly the light switch/dimmer enclosure All the heat sinks need is air to dissipate heat to. Even running heating system air flow kept it cool and I could run dash lights as low as I wanted. I ran PIA 60/65 headlight bulbs to boot. I just always flowed air thru it running HVAC fan.

There is also goodness in upgrading the headlight wiring from the light bulb connectors all the way back to the relay, and run heavy power/ground leads to feed the relay. Your old headlight wiring will be the the trigger or relay operate lead that used to power the headlights. You need another power source with fuse from the battery or Painless Wiring Panel. Easy Peasy!

 

[petersonj]

Relay the headlights. You will not only quit replacing headlight switches, but you will significantly improve headlight performance just by removing the voltage drop through the headlight switch and long lengths of undersized wiring.

I relayed the headlights on my truck just after I bought it new. 357,000 miles and still using the original headlight switch.

- John

 

[Road Dog]

Since you mentioned your 5th wheel, on my 2002 the trailer parking light circuit on the 7-pin connector has a separate relay and fuse. The 4-pin is wired to the vehicle parking lights.