We have a 2005 T&C. Headlights used to come on with several tries, but now won't come on at all. We've tried the high beams which won't stay on once we let go of the switch. We've checked all fuses and replaced the headlights. It still does the same thing. We ended up having to stop at a hotel on a trip due to them not working, and we didn't want to put our kids safety at risk.

Try jiggling your turn signal/ high beam switch. I have seen these fail and cause problems. Not a cheap part either.

Have you checked to see if the bulbs are burnt out or if the low beam fuses are Blown?

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

You wasted time & money knowing you have
no vehicle knowledge

Do you not have a repair shop you found years
ago, like you have several doctors you go to?

Take the car to a shop you have researched
really good

There is not much you can do, Some cars are just that You can get higher wattage bulbs, But in most Provinces & States they are (iligal) to use them, There only for off road use,

Sounds like you may have a bad multifunction switch. I can help you figure this out but you will need a test light or voltmeter and a couple of jumper wires. You will also need to be able to remove the steering column cover to gain access to the switches electrical connectors.

If the above is possible let me know and I'll be happy to help.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Obviously you have a connector which has come partially apart somewhere between the Headlights and the Headlight Switch. Most modern vehicles have several connectors between the Headlight Switch and the Headlights, Start at the Firewall Connector and work forward toward the Headlights making sure all connectors are securely mated. Another remote possibility is that you have fractured the "Low Beam Filaments" in BOTH Headlights. You don't mention how hard you hit the Speed Bump but if it caused the car to "Bottom Out" the front suspension it was a hard enough impact to fracture the filaments. You can use a 12 Volt Test Light at the Sockets for the Headlight Bulbs and see if you are getting 12 Volt power there. If you are in Low Beam position you have fractured the filaments. Check with High Beam too.

Common for the wire harness on the switch to go bad. Inspect the wire harness where it clips on to the switch and look for any signs of damage.

The plastic heats up from the current running through the switch and causes it to melt and then you loose connection caused from melted plastic between the contacts from the harness to the switch.

There is a upgrade to the headlight harness which is larger then the ones that came with the Suburban to address this issues. You can get them at the dealer or NAPA i believe.

Good luck and keep us posted. Thank you for using fixya and stay safe.

Molson02536

as the lights worked when you held the switch in position , check/ replace the light switch

Most likely Relay #46 in the underhood fuse panel is bad, try swapping it with #45 to isolate problem.

Why are you looking for the fuse? High beams not working? low beams not working? Are neither the high or low beams working? Are you sure the bulbs are not burned out? There are 4 fuses for your headlamp system, which one are you looking for?

Please review this article:
Where's The Fuse?