The 2007 Chevy Silverado introduced a split model year: the Classic body style carried over from 2006, and the New Body Style (NBS) started mid-year. Both use different lighting systems, so the fix depends on which one you have. Here’s how to figure it out and fix the DRLs (daytime running lights) step-by-step.
Step 1: Know Your Body Style
If your Silverado has the rounded front end and looks nearly identical to a 2006, it’s the Classic body. If it has a squared-off front, new dash layout, and blockier headlights, it’s the New Body Style (GMT900).
- Classic = Same system as 2003–2006 models (simple relay, fuse, resistor)
- NBS = Controlled by Body Control Module (BCM), fewer serviceable parts
For Classic Style (Early 2007)
1. Check the Parking Brake Switch
If the truck thinks the parking brake is on, it won’t activate DRLs. Make sure the pedal is fully released and that the dash brake light goes off. If not, adjust or replace the switch under the pedal.
2. Shift Into Drive and Test
DRLs only activate when the truck is in gear, headlights off, and ambient light is bright enough. Put the truck in Drive, engine running, and step outside to check for a dim glow from the high beams.
3. Fuse and Relay
Open the underhood fuse box (driver’s side). Look for the DRL fuse (10A or 15A) and the DRL relay. Pull the fuse and check it. Try swapping the relay with a known working one (like the horn or A/C).
If the DRLs come on, replace the relay with something like the ACDelco D1780C.
4. DRL Resistor
This aluminum heat sink behind the grille reduces voltage for the high beams during DRL mode. Inspect it for cracks, corrosion, or disconnected wires. Replace it if damaged.
5. Bulbs
Even if your high beams work, worn 9005 bulbs may not light at DRL voltage. Pull and inspect for discoloration or aging. Swap both bulbs. Try Fahren 9005 LEDs if you want an upgrade.
For New Body Style (NBS) 2007 Silverado
1. DRLs Controlled by BCM
This version uses the Body Control Module to control all lighting. The DRLs are usually the amber turn signal bulbs (front). If they’re out, start with the bulbs:
- Check the 3157/7443 DRL bulbs
- Look for blackened glass or burnt filaments
- Replace with AUXITO LED DRL bulbs
2. DRL Fuses
Check the underhood fuse block and interior fuse panel for DRL-labeled fuses. Consult your owner’s manual or the fuse box diagram for exact locations. Replace any blown fuse.
3. BCM Reset or Programming
If bulbs and fuses are good but DRLs still don’t work, the BCM may need to be reprogrammed or reset. This usually requires a dealer or an advanced scan tool. Some BCMs are known to glitch and lose DRL functions after battery replacement.
4. Headlight Switch Settings
If your truck has automatic lights, make sure you’re not manually overriding DRLs by turning the lights to OFF or AUTO at the wrong time. Try different combinations (AUTO vs OFF) and observe DRL behavior.
Final Tips
For Classic models, the DRL system is easy to repair with just basic tools and a few parts. For the NBS, it’s more BCM-dependent, and problems may require a dealer or scanner. Either way, most DRL failures trace back to one of three parts: bulbs, relays, or fuse.
Start with the bulbs and fuse — they’re cheap and easy. If that doesn’t work, work your way to relays, sensors, or programming needs depending on the version of your 2007 Silverado.
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