1. Identify the Problem:
* Is the door completely locked? If so, try unlocking it using the key in the door, the key fob (if equipped), or the interior door handle.
* Is the latch mechanism itself stuck, or is something blocking it? Look closely at the door jamb and the door itself for any obstructions. Is there something jammed in the striker plate (the metal part on the door frame the latch engages with)?
* Is the problem with the exterior handle, interior handle, or both? This helps narrow down the source of the issue.
* Is it only one door affected?
2. Troubleshooting and Potential Fixes:
* Lubrication: This is often the simplest solution. Use a penetrating lubricant like WD-40 or a specialized door lubricant. Spray it liberally into the latch mechanism (where the handle connects to the latch) and the striker plate. Work the handles repeatedly to help the lubricant penetrate. Wait a few minutes, then try opening the door again.
* Check the linkage: The door handle is connected to the latch mechanism by a series of rods and linkages. These can become disconnected, bent, or rusted. You may need to remove the interior door panel to access these parts. (See step 3 for door panel removal) If you find any broken or bent parts, they may need to be replaced.
* Striker Plate Issues: Examine the striker plate on the door jamb. Is it bent or damaged? Is it properly aligned with the latch? A misaligned striker plate can prevent the door from latching or unlatching. Gently try to adjust it with a screwdriver if it appears misaligned.
* Cable Issues (Less Common): Older Suburbans sometimes use cables instead of rods to connect the handles to the latch. These can stretch, fray, or break. Again, door panel removal is necessary to check this.
* Actuator Problems (Power Locks): If your Suburban has power locks, the actuator motor itself might be failing. This would typically involve a buzzing sound from the door when trying to unlock/lock. This requires more advanced repair, likely involving replacing the actuator.
3. Removing the Interior Door Panel (Necessary for Linkage/Cable Inspection):
This process varies slightly depending on the specific year and trim level. Search online for "1994 GMC Suburban interior door panel removal" to find a video or guide specific to your model. Generally, it involves:
* Removing the screws: These are usually hidden under the armrest, door handle, and speaker cover.
* Disconnecting the window switch and other connectors: Be gentle to avoid breaking the connectors.
* Carefully prying the panel away: Start at the edges and work your way around. Use plastic pry tools to avoid scratching the panel.
4. Replacement Parts:
If you find broken or worn parts, you'll likely need replacements. You can find these at auto parts stores or online. Be sure to specify the year, make, model, and door (driver's side, passenger's side) when ordering.
Important Safety Considerations:
* Disconnect the battery negative terminal before doing any electrical work to avoid accidental shorts or injury.
* Use appropriate safety glasses to protect your eyes from flying debris.
* Be careful when using pry tools to avoid damaging the door panel or other parts.
If you've tried these steps and the door is still stuck, it's a good idea to consult a professional mechanic. They have the experience and tools to diagnose and fix more complex issues.
