Q: the gas, oil, and volt meters do not work on my 2004 GMC Envoy XL

These instrument clusters have been problematic for years. Among other developments, back in 2008 there was a GM Instrument Cluster Class Action Settlement which was applicable to your make and model year, as well as applicable to many other GM vehicles. At present, if you search on the phrase "Envoy instrument cluster repair" in Google you will see evidence of a veritable cottage industry of repair shops and offerings of refurbished clusters that resolve the type of issue you are having and the type of issue that was the focus of the Class Action. So, electrical problems with the cluster are common. Please see this tutorial which will give you a good overview of what is likely to be the problem you are having as well as repair procedures to resolve it. If you don’t want to do your own gauge repair, or you first want to be sure the issue is not elsewhere in the vehicle electrical system, please request service and the responding certified mechanic will determine whether the issue is in the cluster or not and then let you know of your repair options. If the issue is the cluster (again, likely), and assuming you don’t want to replace the stepper motors yourself, usually the most cost effective approach is to buy an off-the-shelf re-manufactured cluster and have the mechanic install it. The refurbishers of these units work in volume whereas a mechanic might get only a couple a year and it is not cost effective to maintain the parts and expertise to just repair a couple a year. I have repaired them though; it is actually easy enough and I encourage you to avail yourself of the tutorial if you want to do your own repair. If not, as noted, just request service and, if required, the mechanic will replace the cluster for you. If the issue is not the cluster, the mechanic will find and resolve the issue. If you have further questions or concerns, do not hesitate to re-contact YourMechanic because we want you to make the most of your repair dollars and help you to get the best possible results.