2017 Ford Explorer Liftgate Not Working? Full Diagnostic Process That Found the REAL Problem
Introduction
When a power liftgate stops working, most people assume the worst—bad module, failed motor, or expensive electronic failure. But as any experienced technician will tell you, diagnosing car problems isn’t always that straightforward.
This case involved a 2017 Ford Explorer with a completely inoperative liftgate, multiple warning messages, and several modules not communicating. At first glance, it looked like a failed rear gate module. But as we dug deeper, the real issue turned out to be something far more fundamental—and far more common.
This is a perfect example of why proper automotive troubleshooting matters and how easily you can go down the wrong path without a solid diagnostic process.
🔧 Recommended Tools for Diagnostics
When you're diagnosing modern vehicles, having the right tools makes all the difference. A basic code reader will only get you so far—you need tools that let you see what’s really going on and test components properly.
Autel MaxiSys MS906 Pro TS Professional OBD2 Scanner (with TPMS & full system diagnostics)
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Power Probe 3 (PP3CSRED) Circuit Testing Tool
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Used daily for checking power and ground circuits and activating components quickly during diagnostics.
Power Probe ECT3000 Circuit Tracer (Short & Open Finder)
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This tool helps locate broken wires or shorts inside harnesses without tearing the vehicle apart, saving time and avoiding unnecessary parts replacement.
Vehicle Overview
The vehicle in question was a 2017 Ford Explorer with approximately 68,000 miles. It came in with a known issue involving the rear liftgate, and a rear gate/trunk module (RGTM) had already been replaced prior to further diagnosis.
Vehicle Concern
The main complaint was simple:
Liftgate completely inoperative
“Liftgate Ajar” message displayed on the cluster
No response from the rear gate module during initial scans
Multiple modules showing communication faults
Additionally, the keypad on the driver’s door (B-pillar) was not lighting up, which introduced another layer of concern.
Initial Inspection & Observations
Right away, several red flags stood out:
The rear gate module was not communicating
Numerous modules across the vehicle showed “no response”
The keypad system was also non-functional
Any time you see multiple modules offline, you have to step back and think bigger than a single component failure. This is where many misdiagnoses happen.
Diagnostic Trouble Codes
Initial scans revealed multiple U-codes, including:
Loss of communication with the rear gate module
Invalid data from the rear gate module
Widespread communication faults across various systems
These types of codes are often symptoms—not root causes.
Step-by-Step Diagnostic Process
At this point, it would have been easy to assume the replacement RGTM was faulty. But that’s not how proper automotive troubleshooting works.
First, network integrity was checked using a resistance test at the diagnostic connector. The reading came back around 60 ohms, which confirmed the CAN network itself was intact.
This was a critical step—it ruled out one of the most common causes of multiple module failures.
Next, attention shifted to power and ground distribution.
When multiple modules go offline, one of the first things you should consider is whether they’re even being powered up. A module that doesn’t have power can’t communicate—simple as that.
A full inspection of the fuse panels was performed, including both the underhood and interior fuse boxes.
That’s where the breakthrough happened.
Key Findings
A blown 5-amp fuse was found in the interior fuse panel. This wasn’t just any fuse—it was feeding multiple body-related systems, including:
Driver Door Module (DDM)
Rear Gate/Trunk Module (RGTM)
Keypad system
Other related modules
Once that fuse was replaced, everything changed immediately.
The keypad lit up
Modules came back online
The liftgate regained partial function
This confirmed the root issue had been a power distribution failure—not a bad module.
Final Diagnosis & Repair Recommendation
After restoring power, the rear gate module was now communicating but stored a calibration-related fault code.
This indicated the module had not been properly programmed.
A Programmable Module Installation (PMI) was performed using factory-level software. Once programming was completed:
The liftgate operated fully under power
Open and close functions worked properly
All related systems returned to normal operation
Final result: Full system functionality restored.
Common Causes of This Problem
This type of issue is more common than many people realize. Some typical causes include:
Blown fuses affecting multiple modules
Wiring damage in door or liftgate harnesses
Improper module replacement without programming
Short circuits causing power loss to control modules
These are exactly the kinds of problems that get overlooked during quick inspections.
Lessons for DIYers & Used Car Buyers
This case highlights several important lessons.
First, never assume a module is bad just because it’s not communicating. Always verify power and ground before replacing anything.
Second, multiple system failures usually point to a shared issue—like a fuse or wiring problem—not multiple bad components.
Third, this is why used car inspection tips matter so much. A quick scan might show communication faults, but without deeper automotive troubleshooting, the real issue can be missed entirely.
A vehicle like this could easily be misdiagnosed, leading to unnecessary parts replacement and wasted money.
Don’t Get Burned on Your Next Used Car
If you’re thinking about buying a used car—or even if you already have one—this is exactly the kind of problem that can slip through the cracks and cost you big money later.
After 35+ years in the automotive field, I’ve seen firsthand how often people end up with vehicles that have hidden issues just like this.
That’s why I put together a simple Used Car Guide to help you understand what to look for and how to avoid making a costly mistake.
It’s a quick, practical guide designed to give you the right mindset and approach before you buy.
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It’s a smart first step toward making a better used car decision.
Disclaimer: Some of the links in this post may be affiliate links, which means I may earn a small commission if you purchase through them—at no additional cost to you. I only recommend tools and products that I personally use or trust in real-world diagnostics.
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