JULY 18, 2025

Troubleshooting the Palfinger PLR Liftgate: Power, Hydraulic, and Electrical Fixes

If your Palfinger PLR tuck under liftgate isn’t operating correctly, you’re not alone. From power issues to hydraulic malfunctions and wiring faults, there are several common reasons a liftgate might stop working. Whether it’s stuck in the up position, won’t lower, or simply refuses to turn on, this guide walks you through field-tested fixes using only verified instructions from Palfinger’s manuals.

• Documentation Resources from Palfinger
• Power Issues: When the PLR Won’t Turn On
• Liftgate Won’t Lower: Common Causes and Solutions
• Liftgate Won’t Raise: Electrical or Hydraulic?
• Wiring and Electrical Checks
• Hydraulic System Checks and Oil Maintenance
• Final Thoughts

Documentation Resources from Palfinger

Information in this article is sourced from Palfinger PLR series manuals and technical guides as well as our Team’s expertise. Always refer to your specific liftgate’s manuals for complete procedures and serial number, model, and year-specific details.

Reference PDFs used:

• Palfinger PLR Owners Manual
• Palfinger PLR Installation Manual
• Palfinger PLR Tuckunder Liftgate Parts Manual

Power Issues: When the PLR Won’t Turn On

Nothing’s more frustrating than pressing a button and getting zero response. If your tuckaway liftgate won’t power on at all, start by ruling out simple issues like a tripped switch or a dead battery.

Start with these steps:

• Confirm the ON/OFF switch is turned on:
• On trucks: inside the cab
• On trailers: on the dock bumper strut (Owner’s Manual, pg. 25)
• Check the circuit breaker on the main battery:
• If the reset tab is exposed, press it back in (pg. 25–26)
• Test the vehicle batteries:
• Fully charge them and measure voltage:
• Flooded: 12.6V
• AGM: 12.8V (pg. 26)
• Inspect the inline fuse on the solenoid:
• Use a 15A fuse only
• Replace if blown—never substitute with higher amperage (pg. 26)
• Ensure proper grounding:
• Check that the liftgate is grounded securely to the chassis (pg. 26)
• Visually inspect for damage:
• Look for frayed wires, corrosion, or disconnected terminals

By working through these checkpoints in order, most electrical power issues can be resolved quickly—no guesswork needed.

Liftgate Won’t Lower: Common Causes and Solutions

When your liftgate won’t come down, it might seem like a major failure—but it's usually a simple electrical signal or valve issue.

Here’s how to diagnose it:

• Visually inspect valves at the cylinders for bending or breakage (pg. 27)
• Bypass the toggle switch:
• Disconnect cable #2 (black, with inline fuse)
• Disconnect cable #6 (yellow/green from toggle)
• Plug #2 and #6 together directly
• If the liftgate lowers, the toggle switch or wiring harness may be damaged
• Test for voltage at the release valve:
• Use a voltmeter while pressing DOWN
• No voltage = damaged cable
• Test the solenoid coil:
• While pressing DOWN, hold a screwdriver near the valve stem
• If there's no magnetic pull, the coil is likely bad

Resolving a liftgate stuck in the down position typically requires checking wiring continuity or replacing a faulty coil—not a full system overhaul.

Liftgate Won’t Raise: Electrical or Hydraulic?

A tuckunder liftgate stuck in the up position usually signals issues in the raise circuit: solenoid, wiring, or motor failure.

Troubleshoot using the steps below:

• Check for valve damage at the lift cylinders (pg. 28)
• Jump cable #2 to the solenoid:
• If the liftgate raises, the toggle switch or harness is the issue
• Listen for solenoid click:
• No click = faulty solenoid or thermal switch
• Click present but no lift = test large studs for voltage
• No voltage = internal fault in solenoid
• Test motor power:
• No voltage at the motor stud = bad solenoid connection
• Voltage present but no movement = worn motor brushes or failed motor

By isolating the fault step by step, most lift-up issues can be narrowed down to a simple component swap.

Wiring and Electrical Checks

Although this Palfinger Liftgate is extremely well built and an industry leader, the PLR’s electrical system is only as strong as its weakest wire or ground. If your liftgate works intermittently—or stops altogether—don’t overlook electrical diagnostics.

Key areas to inspect:

• Ground connections:
• All batteries and power units should be grounded to the vehicle’s chassis (pg. 29)
• Wiring harnesses:
• Look for signs of damage, pinched wires, or poor insulation
• Fuse holders and fuses:
• Only use 15A ATC fuses
• Never “jump” a fuse or use wire to bypass it (pg. 26)
• For trailers: Perform a cross test using a load tester:
• Tests both tractor and trailer charging and grounding circuits (pg. 30)
• Avoid relying only on low-amp voltage tests—they miss weak connections

Electrical issues can cause the liftgate to appear completely dead or behave unpredictably. Careful attention to wiring and fuse integrity can often restore full function.

Hydraulic System Checks and Oil Maintenance

Not all liftgate issues are electrical. When your PLR won’t lift under load or drops unevenly, it’s time to inspect the hydraulic system.

Begin with the basics:

• Check oil level:
• Platform must be fully lowered
• Fluid should be 1.0"–1.5" from top of reservoir (pg. 26)
• Use recommended hydraulic oil:
• Mobil DTE 13M, Chevron AW MV32, or equivalent (pg. 21)
• Inspect for leaks:
• Around the reservoir, valve block, cylinders, and hydraulic lines
• Bleed the system:
• Run all lift functions several times after repairs to purge air (pg. 24)
• Review schematics:
• Gravity Down and Power Down diagrams help ensure correct valve and line configurations (pg. 33–34)

Proper fluid level, regular maintenance, and understanding hydraulic flow are key to keeping your liftgate working reliably. Need some now? Find and purchase lift gate oil today.

Final Thoughts

Troubleshooting a Palfinger PLR tuck-away liftgate doesn’t have to involve trial and error. Whether you’re facing a liftgate stuck in the up position, a power issue, or a faulty solenoid, Palfinger's manuals offer step-by-step procedures that any technician can follow.

At LiftGateMe, we have OEM replacement parts for your liftgate and provide support to get your unit back in working order. If your diagnostics point to a worn wire, damaged switch, or solenoid failure, we’re just a call or click away.