Headlamp switch rheostat for dash lights

[Mr V]

Hi,

I know the eyes are getting older, but I was wondering if anyone else has difficulty seeing the dash gages at night. mine seem to be very dim!

does anyone know if there is a stronger rheostat that would increase the voltage to the monitor lights?

Thank You,

[itdave]

Mine are not that bright either so for that and other reasons, I retired, I avoid driving at night. I will assume that the rheostat is like any normal one in one direction full voltage is applied to the lights in the other the full voltage is dissipated by the rheostat. So unless the rheostat is bad it should be outputting the full chassis battery voltage to the lights. So changing the rheostat will not increase the brightness of the dash lights. One thing that could be going on is that the rheostat is not receiving full voltage or that the wiring in use is not large enough to supply all the lights full voltage. I have had this problem with other 12 volt circuits in my motor home. If Monaco strung a lot of lights off the output of the rheostat with small gauge wire the bulbs may not be receiving the full 12 to 13 volts they need because of the voltage drop in the wire. There also might be an issue with a poor ground for the dash lights. If the lights are receiving full voltage the only other things that could help brightness is more lights or higher wattage bulbs.

If you are handy with a volt meter and can get to the back of your dash panel you could do some checking on voltages coming into the rheostat, going out of the rheostat as you rotate it and what is getting to the light bulbs. Remember to use the a ground on one of the light bulbs when doing the check. If you find low voltage first check that the ground on the light bulb has zero resistance to the actual chassis ground.

Hope this helps you figure out if there is a problem and if there is where it is. I have some thoughts on correcting low voltage to the rheostat. If it is a bulb issue maybe someone can give you some pointers on replacing burnt out bulbs or installing brighter ones.

With all the work involved I vote for driving during the day. Good Luck

[Mr V]

Thank You for the detailed reply, I will try getting some readings with a volt meter!

Appreciate your help

[Diplomat Don]

MR V.....Mine are the same way, but I've never dug into the problem. My fix was to have my eyeglass doctor make me a pair of glasses just for driving the M/H. The bifocals are set to read the gauges clearly from 40" away. They work very well.

[NMBeemercouple]

The instrument lights on our coach are very dim as well. I thought it might be the controller, but sounds like even the newer models have this characteristic. I've done the same with the bifocals when driving at night, although mine are off-the-shelf clear safety glasses with 125 magnifiers on the bottom of the lens.