Subaru Forester Rear Wiper Not Working: Causes, Diagnosis, and Fixes

What a Rear Wiper Failure Usually Means

If your Subaru Forester rear wiper not working issue appeared suddenly, the cause is often electrical, mechanical, or related to the rear wiper motor assembly.

Because the rear wiper depends on a short wiring path, a switch signal, and a small motor, even one failed part can stop the system completely.

The good news is that most rear wiper problems can be narrowed down with a few basic checks before replacing expensive components.

Knowing where the failure is happening saves time and helps avoid unnecessary parts replacement.

Common Symptoms of a Forester Rear Wiper Problem

Rear wiper failures do not always look the same.

In many Subaru Forester models, the problem may show up as one of the following:

• The rear wiper does not move at all.
• The wiper works intermittently.
• The wiper moves slowly or struggles.
• The wiper stops in the middle of the glass.
• The washer sprays but the blade does not wipe.
• A fuse blows repeatedly after activation.

These symptoms help point toward the likely fault.

A silent wiper often suggests an electrical supply issue, while a wiper that clicks or stalls may indicate a seized linkage or failing motor.

Start with the Simplest Checks

Before removing trim or testing circuits, confirm the basics.

Many rear wiper complaints come from simple issues that are easy to overlook.

Inspect the rear wiper blade and arm

A worn or frozen blade will not usually stop the motor from running, but it can overload the system.

Check for ice buildup, bent hardware, or a blade that is jammed against the glass.

Verify the rear glass and hatch area

Make sure the rear hatch is fully closed.

On some vehicles, related body control logic or wiring movement around the hatch can affect rear wiper operation.

Also check for visible damage to the rubber boot where the wiring harness enters the hatch.

Test the washer system

If the rear washer also fails, the issue may be in the shared stalk switch, fuse, wiring, or washer pump circuit.

If the washer works but the wiper does not, the fault is more likely isolated to the wiper motor, linkage, or control signal.

Check the Fuse and Power Supply

One of the first diagnostic steps for a Subaru Forester rear wiper not working is checking the fuse.

A blown fuse can disable the rear wiper motor completely.

Use the owner’s manual or fuse box cover diagram to locate the correct fuse for the rear wiper or rear washer-wiper circuit.

Replace it only with the exact amperage rating specified by Subaru.

If the new fuse blows immediately, there is likely a short circuit, a locked motor, or damaged wiring.

If the fuse is intact, test for voltage at the rear wiper motor connector when the switch is turned on.

A multimeter helps confirm whether the motor is receiving power and ground.

Test the Rear Wiper Motor

The rear wiper motor is a common failure point, especially in older Foresters or vehicles exposed to moisture and road salt.

Corrosion can damage the motor internals or electrical connector.

To test the motor, disconnect the wiring connector and check for battery voltage while the rear wiper switch is engaged.

If power and ground are present but the motor does not run, the motor itself is likely faulty.

If there is no power, the problem is upstream in the switch, fuse, wiring, or control module.

Some motors may still make noise without moving the blade.

That usually points to an internal gear failure or a seized pivot mechanism.

Look for a Seized Linkage or Pivot Arm

Not all rear wiper failures are electrical.

The linkage and pivot shaft can seize from corrosion, dried grease, or water intrusion.

When this happens, the motor may try to run but cannot move the arm.

Signs of a mechanical seizure include:

• A humming sound from the rear hatch when the wiper is activated.
• A motor that gets hot quickly.
• A blade that moves only slightly or not at all.
• A blown fuse after the motor tries to start.

If the pivot is stuck, the assembly may need to be removed, cleaned, lubricated, or replaced depending on the extent of the corrosion.

In many cases, replacing the complete rear wiper motor and linkage assembly is more practical than rebuilding worn parts.

Inspect the Rear Hatch Wiring Harness

Forester hatch wiring is another frequent source of intermittent rear wiper issues.

The harness flexes every time the hatch opens and closes, which can eventually break wires inside the insulation.

Check the wiring boot between the body and rear hatch for cracked insulation, pinched wires, or broken conductors.

Symptoms of a damaged harness may include intermittent wiper function, rear washer failure, rear defogger problems, or multiple electrical issues at the liftgate.

A continuity test with a multimeter can reveal broken wires that are not visible from the outside.

If you find damaged wiring, repair it properly with soldered joints or approved automotive repair methods to preserve flexibility.

Consider the Wiper Switch or Control Module

If the fuse, motor, and wiring all test normally, the issue may be the switch on the steering column or the body control module logic that commands the rear wiper.

The switch can wear out internally, especially if it is used often or exposed to contaminants.

Possible switch-related signs include:

• The front wipers work, but the rear wiper does not respond.
• The rear washer activates inconsistently.
• The rear wiper works only in certain switch positions.

Modern Forester models may route some rear wiper commands through body electronics rather than a simple direct circuit.

In those cases, scan tool data can help confirm whether the module is receiving the switch input and sending output to the motor.

Diagnose Intermittent Rear Wiper Operation

Intermittent faults are often caused by loose terminals, corrosion, or wires that fail only when the hatch moves.

To diagnose this type of problem, repeat the wiper test while gently moving the hatch wiring harness and watching for changes.

If the wiper starts and stops as the harness moves, the repair focus should be on the affected wire section or connector.

If tapping the motor or moving the arm changes the behavior, the motor or linkage is more likely at fault.

Intermittent operation can also come from weak battery voltage or poor grounding.

A weak battery is less common, but low system voltage can make an aging rear wiper motor stall.

When to Replace the Rear Wiper Motor Assembly

Replacement is usually the right choice when the motor receives proper power and ground but still fails to run, or when the linkage is seized beyond practical repair.

Many technicians replace the complete assembly because it is faster, more reliable, and reduces repeat labor.

Before installing a new part, compare the old unit with the replacement and inspect the connector, pivot, and blade arm.

If the original failure was caused by corrosion or a wiring fault, address that root cause so the new motor does not fail early.

How to Prevent Rear Wiper Problems on a Subaru Forester

Regular maintenance can extend the life of the rear wiper system and reduce the chance of another failure.

• Clean the rear glass and wiper blade regularly.
• Do not run the rear wiper when it is frozen to the glass.
• Inspect the hatch wiring boot during routine service.
• Replace worn blades before they drag or chatter.
• Use the rear washer periodically to keep the system moving.

Simple preventive habits help protect the motor, linkage, and wiring from avoidable stress.

In cold climates, lifting the blade away from the glass before freezing weather can also reduce strain on the pivot and motor.

What to Check First if the Rear Wiper Still Won’t Work

If your Subaru Forester rear wiper not working issue remains unresolved, focus on the most likely failure path in this order: fuse, rear hatch wiring, motor power and ground, linkage movement, and switch input.

This sequence covers the majority of rear wiper failures and helps isolate the fault without guesswork.

For drivers who want a fast repair decision, the key question is whether the motor is being commanded and powered correctly.

Once that is known, the repair usually becomes straightforward.