Just discovered that both high beams are not working. Regular lights ok. When switch to high beam both go off. I know some bulbs have two filaments, is this the case for this car?
Are the bulbs burnt out or something else is wrong?
I would look at the unit that controls your high beams. You could remove the headlight and then check the voltage at the high beam terminal when high beam is selected. If it has 12VDC then it’s a headlight bulb problem. If not…it’s a problem with the headlight high beam control. I suspect the latter only because both high beams are out.
Once you check the voltage like missileman says, try to back track the wiring to see where the voltage break is. This can be a PITA. The headlight switch is a common problem on Wranglers, but very easy to replace. The high beam switch is not too bad to replace. My sons Jeep had a similar problem, turned out to be at the fuse box, where the wire going out from the fuse looked like it was intact but when I pulled on it with needle nose pliers it was loose, had corroded away. Not sure about the Rubicon, but on the Wrangler it is easy enough to get the fuse box off and check underneath.
Do you even know if you jeep has 2 or 4 bulbs ( seperate bulbs for high and low) for the headlights? Have you even looked? Have you tried new bulbs? I don’t even think about problems until I at least try the obvious things. And since the head light will be out so you can get a new one might as well check for voltage.
Rubicon is the off road package, locking differentials, 4:1 transfer case ratio, different axles, wheels, tires and shocks. First offered in 2003, “Rubicon” doesn’t tell us if it is a TJ or JK series. Knowing the model year would allow us to research common problems.
You have not stated the year model but just looking at a random Wrangler schematic it could be that the dimmer switch has failed as both high and low beam appear to have a common power source through the headlamp switch.
A test light or Voltmeter should be used to verify power at the lamp connectors with the dimmer being checked on both the low and high beam positions. Power in one blade and not the other would likely mean the dimmer has failed.
If both are out, I’d suspect the hi-lo beam switch first. Do the high beams come on with the headlights on if you pull the switch forward for “flash to pass”? Also, check all your fuses.
If you haven’t first verified the high beam filaments are good I suggest you do that before you go looking for trouble you may not find, just because both filaments are burned out.
Agree w/ @Cougar above, the first thing is to check to see if the high beam filaments are burned out. It wouldn’t be that unusual for both high beam filaments to burn out in the same time frame. The high beams draw the most power and therefore get the hottest, making them the first to go. What I’d do in this situation first is remove the electrical connector (for each side) and use an ohm-meter to measure the resistance of both filaments. If it turns out both high beam filaments are burned out, all you need to do is install replacement bulbs and you’re done.
any additional advice for my situation? when i try and go to high beam, all the lights go off and stop working completely. i assume it’s the dimmer switch but would like to hear how to verify before we start changing things.
To verify it check the voltage on the high beam wire at the switch. You should have voltage on that lead when the high’s are selected. Does the flash section section of the switch work?