Gmc Sierra Tailgate Won’t Open [Complete Guideline!]

The GMC Sierra is a renowned light-duty truck. You can efficiently load and unload heavy material in this truck, according to your needs.

The tailgate is super important when it comes to loading cargo in your Sierra. But, users may find their GMC Sierra tailgate stuck at times.  

So, what to do when the Gmc Sierra Tailgate Won’t Open? 

Damaged cables, electrical issues, problematic locks, and loose/faulty tailgate handles can cause this issue. For the solutions, firstly, replace the cables of the tailgate mechanism. Secondly, check and replace the lock assembly of the tailgate. Thirdly, the handle of the tailgate needs replacement. Finally, you have to check, repair, and replace all the electric wiring, switches, etc.

You’ll need more information to successfully diagnose the reason and solve them. For that, read till the end of this article.

4 Reasons Why the Gmc Sierra Tailgate Won’t Open

There could be multiple reasons behind the GMC Sierra tailgate not opening. I’ve mentioned every possible reason, their symptoms, and the solution for this issue. Take a look-

Reasons	Symptoms	Solutions
Damaged Tailgate Cables	Tailgate Not Opening or Closing Properly	Replace the Cables of the Tailgate
Problematic Lock	Tailgate Lock Not Working	Check the Lock and the Assembly of the Tailgate
Loose or Faulty Tailgate Handle	Tailgate Handle Not Working	Replace the Handle of the Tailgate
Electrical Issues	MultiPro Tailgate Feature Not Working	Check, Repair, and Replace the Electrical Parts

Problem 1: Tailgate Not Opening or Closing Properly

This is one of the most common tailgate problems out there. When the cables of the tailgate are too loose or stop working, it can get frustrating.

The whole tailgate mechanism fails due to this. Even the tailgate of the Volvo Xc70 doesn’t open because of this reason.

This happens even in the later models of the GMC Sierra, where the electric tailgate has been introduced. Any damaged, bent, loose, or corroded rod can result in this problem.

Solution:

The main solution to this problem is to replace the cables of the tailgate.

Here’s a step-by-step guideline on replacing the cables of the tailgate:

• Firstly, make sure you turn off the GMC Sierra first. Then, start with removing the existing cables. Use pliers to pull out one end of the hooks of the tailgate cables.
  
• Then, unscrew the other end of the cable. For this step, use a ratchet and socket wrench.

Finally, start installing the new cables. Attach one end of the new cable to the hook of the latch mechanism. Also, screw in the other end of the cable. Do this for every cable on the back of your GMC Sierra!

Make sure the cables are tight. They must not be too loose or too stiff. It might damage them quicker!

Problem 2: Tailgate Lock Not Working

The tailgate lock helps the tailgate lock in place. If the tailgate lock stops working, the tailgate may just be stuck. Additionally, it can never lock in place and hang freely too! This is both annoying and dangerous at the same time.

Tailgate locks can get damaged and break with time. The locks are the most used component in the tailgate because you have to unlock the tailgate frequently.

Alternatively, they can wear out to the point that they stop working. The disengaging and releasing function of the lock fails to do its work. This is a common reason as well! For example, the tailgate of Ram won’t open because of this reason. 

Solution:

For fixing this issue, replacing the tailgate lock is a good idea. Here are the steps to replacing the GMC Sierra lock-

• Start off by disconnecting the battery from your truck. You don’t have to physically pull out the battery; disconnecting the terminals will do.
  
• Next, locate the tailgate lock assembly. It is typically situated on the interior of the tailgate. The assembly can be accessed by removing any panels and covers that may be obstructing it.
  
• Now, after gaining access to the lock assembly, carefully disconnect any wiring harnesses or linkages that are connected to it.
  
• After that, remove the nuts or screws that hold the lock assembly in place. You can use a set of screwdrivers to remove the screws quickly. You can do this by using either a wrench set or a screwdriver.
  
• Then, start replacing the old lock assembly. Be careful and install the new lock assembly in the same location as the old one.
  
  Secure the new lock assembly with the bolts or screws that were previously removed.
  
• Finally, reconnect all the wiring harnesses you disconnected prior to hand. Also, reconnect the battery of the truck so that the tailgate mechanism gets power.
  
  Now, the tailgate lock should work just fine!

Problem 3: Tailgate Handle Not Working

The tailgate handle of the GMC Sierra is used to disengage the lock when opening the tailgate. If the handle is somehow gotten loose, it won’t disengage properly. That will result in the tailgate handle not working and the tailgate won’t open.

Tailgate handles lose tension over time in general, but any kind of damage can ruin its mechanism. The handle not working can create problems for tonneau covers. For instance, problems regarding the Lomax tonneau covers are evident for faulty handles.

Solution:

To solve this issue, you have to replace the lock. Follow the steps below-

• First, park the GMC Sierra on level ground and activate the parking brake.
  
• Then, remove the front handle cover and unhook the rods that connect the two latches.
  
• After that, unscrew the bolts for the locking mechanism. Then, take the locking mechanism out.
  
• Finally, insert the new locking mechanism and secure it via the bolts.

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Problem 4: MultiPro Tailgate Feature Not Working

This problem here is an upsetting one. The MultiPro feature in the tailgate is a super smart and efficient addition by GMC. 

The tailgate issue also occurs in older models of GMC Sierra, where there’s no MultiPro feature. This problem mainly happens due to electrical issues inside the GMC Sierra tailgate. The fuse box should also be checked regularly for this one.

Also read: How To Open Truck Bed Cover Without Key? Answered!

Solution:

To fix this problem, you have to repair and replace the electric components of your GMC Sierra. Here are the steps to do so-

• First, find the fuse box of your GMC Sierra. There should be fuses for all the electric components and mechanisms of the truck.
  
  Inspect all of the switches individually and look for blown, burnt, or melted fuses. If you see any, replace them with new fuses immediately.

Then, you have to check all the wiring connections. For the GMC Sierras with MultiPro tailgate, check the wiring under the bed lining.

Behind the bed lining panel, there are different switches for different electric mechanisms. Check the switches too. And if you want a manual release of the tailgate, pull on the small metal lever. It should be on top of the switches.

Additionally, check the wiring on your truck engine as well. Corrosion, dust, or any kind of build-up can really mess up the electrical connections. If any of the connections look damaged, replace them.

• Next, check for power in the tailgate release mechanism. You can use a multimeter to check if there’s any voltage in the wiring. If there’s no voltage, replace the wires and the switches.
  
• Finally, check the inner gate switch to see if it’s working. If it’s not, replace the switch.

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Frequently Asked Questions (FAQs):

Read also: How To Patch A Hole In A Tonneau Cover?

Endnote

Hopefully, now you know the reasons and solutions why your gmc sierra tailgate won’t open. 

If you are not experienced with automotive repairs, don’t worry. In such situations, you can seek the assistance of a professional mechanic. They’ll perform this repair correctly and safely.

Best of luck.

Read also: How To Fix Tonneau Cover Latch?