DodgeForum.com

Dodge Ram 2009-Present: Headlight Problems

If one or both of the headlights in your Dodge Ram aren’t working, chances are one of the major electrical components in your truck might need to be fixed or replaced. To learn how best to determine which one it might be, read through these quick and easy troubleshooting suggestions.

By Jeffrey Bausch - July 24, 2015

This article applies to the Dodge Ram (2009-present).

Have you noticed a general dimming of your headlights? Maybe one or even both of your headlights don’t go on all the time. Malfunctioning headlights can be a real headache to deal with. Fortunately, figuring out the problem is actually pretty easy. A malfunctioning headlight is generally the result of a failure of a component within the car’s electromechanical system. To learn how to determine which part is failing in your car, read through these quick and easy troubleshooting steps.

Figure 1. Properly functioning headlights.

Materials Needed

  • New headlight bulbs (as necessary)
  • New connector system components (as necessary)
  • New charging system components (as necessary)
  • Voltmeter

Step 1 – Check the bulbs

This is probably the most oft-cited example of a malfunctioning headlight, but it’s also the easiest one to diagnose. Bulbs, as we all know, have a limited life, and this varies depending on hours of use, how much vibration they’re subjected to, and other things. Check the bulb’s filament to see if it’s still in place/not burned out. If you find something wrong, just replace the bulb.

If you don’t find anything physically wrong with the bulb, check the electrical connector on the back of the headlight for damage/corrosion, and to make sure it’s not loose.

Figure 2. Check the bulb filament.

If the bulbs are all in good condition, then proceed to Step 2.

Step 2 – Check the connector system

If both headlights do not work, you’ll want to inspect the system’s relay, fuse, module, headlight switch, dimmer switch, and wiring fault. It’s a lot, so you’ll want to start with the fuse since that’s the easiest of the components to go. If it’s blown, just replace it with a new one. If the new one blows right away, then there’s a short in the headlight circuit that you’ll need to have fixed.

If the fuse is fine, use a volt meter to check the power fuse. No reading at the power fuse indicates a wiring fault possibly at the fuse block, or in the wiring between the fuse block and battery.

If the power fuse is fine, check the headlight relay. You can do this by pulling it out and giving it a slight shake. If anything rattles, you need to replace the relay.

If the relay is okay, check the headlight switch. This component is subject to a lot of wear and tear, so there’s a good chance it might need to be replaced. You can find the switch by removing the Ram’s steering column, but do not test it out without first disconnecting the battery. Next, wait at least 10 minutes for the capacitors in the airbag circuit to discharge before investigating.

Figure 3. Look over all the connections.

If all connections are sound and the headlight switch is functioning, then continue on to Step 3.

Step 3 – Check the charging system

By the charging system, Dodge is referring to the alternator and the drive belt. You can do this by having the engine run idle, and running a volt meter over the charging system. The voltage over the battery should be about 14 volts. If, however, it is less than 13 volts, there’s something wrong with the system, and your headlights aren’t receiving enough power.

Figure 4. Check the alternator and the belt by using a volt meter.

Related Discussions