1996-1999 GMC K1500 Hazard Warning and Turn Signal Flasher Guide
Having trouble with your turn signals or hazard lights? Your flasher relay is the most likely cause.
- The flasher relay on the 1996-1999 K1500 controls both turn signals and hazard lights.
- Failure symptoms include lights that stay on without flashing, or lights that don't work at all.
- Replacement is very easy, located under the driver's side dash, and is a great DIY task.
- If you use LED bulbs, you must install an electronic LED-compatible flasher to prevent hyper-flashing.
Is Your K1500 Flasher Failing?
A bad flasher relay on a 1996-1999 GMC K1500 will cause obvious problems with your lights. Because this single part controls both the turn signals and the hazard lights, a failure often affects both systems. You might notice one or more of these issues:
- No Flashing: The most common symptom is turn signals or hazard lights that light up but do not flash.
- Complete Failure: Neither the turn signals nor the hazard lights work at all.
- Stuck On: The turn signals or hazard lights will not turn off, even when the switch is disengaged.
- Intermittent Clicking: Some owners report hearing the flasher relay clicking randomly 🎬 Watch this guide to identify and test common flasher symptoms. even when the turn signals or hazards are not activated.
Recall Information for 1999 Models
While the flasher relay itself was not recalled, some 1999 GMC models were part of a recall (NHTSA Recall 01V-364) for a defective hazard switch inside the multifunction switch assembly. This could cause the brake lights and hazard lights to fail. While this recall targeted vehicles built after September 1999, it's a related issue to be aware of for late-model-year 1999 trucks.
Choosing the Right Aftermarket Flasher
For a straightforward part like a flasher relay, an aftermarket replacement is a reliable and cost-effective choice. The original equipment (OEM) brand is ACDelco, but quality aftermarket brands offer comparable performance for less money.
- Standard Motor Products (Standard Ignition): This is a well-regarded aftermarket brand known for producing quality electrical components that meet or exceed original specifications. Their products are widely available and offer a good balance of quality and price.
- ACDelco (OEM): As the original part supplier for GM, ACDelco offers a direct replacement that is guaranteed to fit and function like the original. However, it typically comes at a higher price point.
Pro Tip: If you have upgraded or plan to upgrade your truck's exterior lights to LEDs, you must use an electronic, LED-compatible flasher relay (like the EP29 model). A standard thermal flasher will not work correctly with low-draw LED bulbs and will cause them to flash too quickly (hyper-flash) or not at all.
Replacement Cost
Replacing the hazard flasher is an inexpensive repair. The part itself is affordable, and if you choose to have a shop do the work, labor costs are minimal due to the ease of access.
| Part Source | Estimated Cost |
|---|---|
| New OEM (ACDelco) | $40 - $50 |
| New Aftermarket (Standard Ignition) | $16 - $30 |
| Shop Labor | $50 - $100 |
Frequently Asked Questions
Where is the hazard flasher located on a 1996-1999 GMC K1500?
The flasher relay is located under the driver's side dashboard, typically in a convenience center or relay block near the emergency brake pedal or steering column. You may need to remove the lower dash panel (knee bolster) to see and access it.
Is this a difficult part to replace myself?
No, this is a very easy DIY job. It requires no special tools and is a simple plug-and-play replacement. After removing the lower dash panel, you just unplug the old relay and plug in the new one. The entire process should take less than 30 minutes.
🎬 Follow this video to locate and replace your flasher relay.My turn signals don't work, but my hazards do. Is it still the flasher?
It's possible, but less likely. Since both systems use the same flasher, a complete failure usually affects both. If only one system is malfunctioning, you may have an issue with the multifunction (turn signal) switch in the steering column or the hazard switch button itself. 🎬 See how to troubleshoot turn signals that won't blink. However, given the low cost of the flasher, it's often the first part to replace when troubleshooting.
What is the difference between a thermal and an electronic flasher?
A thermal flasher uses the heat generated by the electrical current flowing to the bulbs to make the circuit blink. An electronic flasher uses a solid-state timer circuit. Electronic flashers are required for LED bulbs because LEDs don't draw enough power to operate a thermal flasher correctly.
Helpful Videos
Technical Specifications
OEM Part Numbers: 11516051
Electronic Combination Flasher, 4-Pin
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- GMC K1500: