If you own a GMC Envoy built between 2003 and 2004, the NHTSA recalled your vehicle for defective flasher relays. If you own one of these vehicles, you can simply call your dealership and they will replace the flasher for you free of charge under the recall. However, if you own an Envoy made in any other year and your flashers do not work, you must replace the relay on your own. You could take it to the dealership and have them do it, but since your vehicle is not within the recall years, you will pay for it. The alternative is to replace the relay on your own.
Pull the cover off the closeout/insulator panel using your fingers. The panel is under the driver's side dash panel.
Remove the bolt that secures the flasher module inside the closeout/insulator panel using a socket and ratchet.
Disconnect the flasher module from the wiring harness it connects to.
Connect the new module to the wiring harness.
Secure the module to the closeout/insulator panel using the bolt, socket and ratchet.
Place the closeout/insulator panel cover onto the panel, and push it into place.
