Electric Tarp Motor Not Working? What to Check First and How to Open the Tarp by Hand

Voltage readings have to be taken with power on. For those, keep your hands and tools away from anything that moves and keep everyone else back.

Why did my electric tarp stop working, and what do I check first?

A lot of the time, an electric tarp stops working because power isn't getting to the motor. Brandon Childress, our Tarp Systems Foreman, has installed tarp systems here since 2012. He says of a system that won't run, "A lot of times it comes down to connection."

1. The battery and its terminals.

2. The circuit breaker.

3. On a trailer, the tarp system's two-pole plug at the front of the trailer.

4. The relay or solenoid. This is the part that sends battery power to the motor when you press the switch, and it reverses that power to change the tarp's direction.

5. The wiring from the relay or solenoid to the motor.

6. The motor.

A test light will show whether power is getting through a breaker or reaching a plug. Most of the other checks ask for a voltage number, so you need a multimeter for those.

A connection can show 12 volts on a meter and still be the problem. Corrosion can let 12 volts through while nothing is running. Then the voltage drops when the motor tries to pull current.

Don't test with a battery charger as the power source. If the trailer is unhooked and you run the tarp off a charger to test it, the result won't tell you anything. Shur-Co and Thunderstone both say a charger alone is not a valid power source and will cause abnormal operation. Use a 12-volt truck battery.

The exact steps, voltages and code tables for Roll-Rite, Shur-Co and Thunderstone systems are further down, each under its own heading.

If the tarp runs from the buttons on the control box or keypad but not from the remote, the power and the motor are fine. The remote may have lost its pairing with the receiver. Our instruction and troubleshooting page has the videos for programming a Roll-Rite remote again.

Regular upkeep is how you find corroded and loose connections before they stop the tarp. Our electrical tarp safety and maintenance page covers it.

Does your electric tarp have a manual override?

A manual override lets you roll an electric tarp open or closed by hand with a crank when the electrical side quits. On the electric systems we install, we add a splined shaft to the roll pipe so a crank can go on it. To use it, pull the main shear bolt up by the motor to disengage the motor, then put the crank on the shaft. We engineered it because customers asked for a failsafe, so they're never stuck at the grain elevator with a tarp that won't open.

If we installed your electric system, it may have one. Check the roll pipe for a splined shaft, which looks like the end of a PTO shaft. A Roll-Rite electric tarp system on an end dump trailer can have one too, if a Brumleve manual override kit was added to it.

If you find the splined shaft and haven't used the override before, call us at (217) 857-3777 before you put a crank on it, and we'll go over it for your system.

How to open an electric tarp with no manual override

If your electric tarp has no manual override, we have no hand method to give you, whatever the brand. On a Roll-Rite system you can run the motor by bypassing the relay. On other systems, the tarp moves again once you find and fix the fault.

Roll-Rite: bypass the relay

The bypass runs the motor without the relay or the remote. Brandon shows how in his video, Bypassing a Roll-Rite electric tarp system, which is also on our instruction and troubleshooting page. Watch it before you try this.

The bypass is done with power connected, so the wires you handle are live. The tarp starts moving the moment the wires you took off touch the other pair. Keep everyone away from the tarp and the arms.

1. Take out the four screws on the box that holds the relay.

2. Lay the box down so you can get to the back side of the relay.

3. Find the two pairs of wires. Two come in from the plug and are your power, one positive and one negative. The other two go up to the motor.

4. Take two of the wires off and touch them over to the other pair, the way Brandon does in the video.

5. Listen to the motor to tell which way the tarp is going. Which wire touches which sets the direction. One way opens the tarp, and swapping the two wires around closes it.

The bypass works when the failed part is the relay or the RF unit, which is the receiver for the remote. It does nothing for a bad motor.

Brandon says it is uncommon to need the bypass, and that it is for emergencies only. Once the tarp is where you need it, call us and we'll help you work out what failed.

Shur-Co, Thunderstone and other systems

Brandon's bypass is for a Roll-Rite relay. We have no bypass steps for any other brand, so don't try it on another brand's wiring.

Use the steps for your system to find the fault. If the tarp has to move before you can do that, call us at (217) 857-3777.

Electric tarp motor troubleshooting steps by system

Use only the steps for your own system. The voltages and flash codes are not the same from brand to brand: five flashes means over voltage on a Roll-Rite Rite-Touch module and under voltage on a Thunder 7000 keypad.

The steps use a few names for one part. Shur-Co's "dual-pole power connection" and Thunderstone's "2-pole power cord" and "2-pole receptacle" are the tarp system's own two-pole plug at the front of the trailer.

Roll-Rite Rite-Touch module

The Rite-Touch module is a Roll-Rite relay with an LED on it. The LED flashes a code, and most of the codes report a fault. These codes apply only if the relay on your Roll-Rite system is a Rite-Touch module. As a rule, the module will not operate while the LED is flashing.

The "load" in the 7-flash code is the motor. "No load attached" means the module doesn't see a motor connected to it. The 7-flash code has three possible causes:

1. Bad connection between module and motor. Check for loose or corroded connections, or a bad motor (for example, worn brushes).

2. Motor lead shorted to ground. Check for bare or pinched wires between the module and the motor.

3. Damaged module. This can happen if the module is wired improperly or if arcing occurs across the terminals. There is a test for it. Call us and we'll go through it with you.

If the tarp runs one way only, check for moisture or contamination between the module spade terminals. Clean them and add dielectric grease.

Shur-Co ShurLink EZR and Pro

ShurLink is the remote and receiver that control a Shur-Co motor system such as the 4500 HD. There are two ShurLink remotes, the EZR and the Pro, and each remote's manual has its own troubleshooting steps. The EZR remote runs on two AAA batteries and has channel indicator lights. The Pro remote has a display screen and a charging cradle.

The receiver box is the control box mounted on the trailer, with buttons on it for running the tarp. Press one and listen. Whether the solenoid inside the box clicks tells you which steps to follow.

ShurLink EZR: won't run from the remote or the receiver box buttons, and there is no loud click from the receiver box

1. Make sure the trailer master disconnect switch, if equipped, is On.

2. The circuit breaker may have tripped. Wait 15 seconds and try again.

3. Check for loose or corroded connections between the battery and the solenoid in the receiver box.

4. Check for low system voltage: measure between the positive (+) and negative (-) posts on the solenoid in the receiver box. With the truck off it should read 12.5 to 12.7 volts. A negative reading means the power wires are hooked up backwards.

ShurLink EZR: the solenoid clicks loudly or chatters, but the motor does not turn

1. Bypass the circuit breaker in the battery box and try again. If the problem goes away, the breaker was fatigued or corroded and should be replaced.

2. Make sure battery connections are tight and free of corrosion, and inspect all wires between batteries. Verify 12.5 to 12.7 volts with the truck off, measured on the battery the system is connected to.

3. Inspect the dual-pole power connection at the front of the trailer and replace it if corroded. Take the connector apart to check that the set screws inside are tight and corrosion-free and that no wire strands are short-circuiting. Apply dielectric grease (not black grease) to the metal contacts.

4. Inspect the wiring between the dual-pole connector and the receiver box solenoid. Replace corroded wires and check for cuts in the insulation; copper wire corrodes quickly once the insulation is cut.

5. Disconnect the motor from the back two solenoid posts (marked In and Out). Press and hold OPEN or CLOSE to engage the solenoid. If it does not measure at least 12.5 or -12.5 volts between the back two posts while engaged, the solenoid is damaged.

6. If it does measure at least 12.5 or -12.5 volts with the motor wire disconnected, the motor may be damaged or there may be a short in the motor wire between motor and solenoid.

A negative reading is normal on the In and Out posts in step 5. The solenoid reverses polarity on those two posts to run the motor the other way, so the meter reads positive in one direction and negative in the other.

A quick test for the power wiring on an EZR system: disconnect power from the truck and run jumper cables from a vehicle directly to the solenoid, positive cable to the solenoid positive post (+) and negative cable to the negative post (-). If the system runs normally, the problem is in the wiring supplying power to the solenoid.

ShurLink Pro: won't run from the gray receiver box buttons, but it clicks, or it stutters

1. Try power from a different 12-volt battery; there may be a bad battery or connection.

2. If a battery charger or power supply is powering it, hook to a truck battery and try again.

3. Remove the gray cover and check the green and yellow wires at the solenoid.

4. Check wiring for corrosion, including any circuit breaker near the truck battery. Corrosion can let 12 volts reach the receiver while the voltage drops under load. Bypass the circuit breaker and test to rule out internal corrosion.

5. Check every encoder wire between motor and receiver for cuts and tight connectors; black encoder wire always to black. On 4500 HD systems, check that the weatherpack connectors (one near the motor, one in the kingpin area) are snap-locked.

6. Verify 12 volts at the motor while an operational button is held. If there are 12 volts and the motor does not run, there may be a motor problem. If it drops below 12 volts, check the wiring for corrosion or a bad truck battery; start the truck and try again.

7. The receiver or solenoid may be damaged.

The encoder wires in step 5 run between the motor and the receiver, and Express Mode and travel stops need them. The operational buttons in step 6 are OPEN and CLOSE.

ShurLink Pro: won't run from the gray receiver box buttons, and there is no click

1. Remove the gray cover and verify 12 volts reach the motor control module. The meter should read +12, not -12, with the red lead on the module's red wire ring terminal and the black lead on the black wire ring terminal.

2. The receiver may be damaged.

Thunderstone Thunder 7000

On a Thunder 7000, which steps you follow depends on whether the keypad powers on. The inner control box is in the nose of the trailer, and the tarp system circuit breaker is near the tractor battery.

The tarp system will not power on

1. Make sure the 2-pole power cord is plugged into the trailer and has the proper polarity and voltage to the tarp system. Vertical plugs are positive on top. Horizontal plugs are positive to the roadside.

2. Check that the tarp system circuit breaker near the tractor battery is passing power, using a voltmeter or test light. Replace it if necessary.

3. Turn on the tarp system by pressing OPEN and CLOSE on the keypad controller together for 3 to 5 seconds, until the LED and buttons light up.

4. Test the remote by pressing OPEN and CLOSE on the remote together for 3 to 5 seconds, to verify whether the keypad buttons have failed.

5. Check for grease, dirt, and corroded connections at the battery terminals, the circuit breaker, and the trailer power receptacle plug and outlet.

6. Check for proper voltage (12 to 14 volts) on the back side of the 2-pole trailer receptacle. Also check it for corrosion and looseness.

7. Check the communication cable between the inner control box and the keypad controller for a proper connection.

8. Unplug trailer power from the 2-pole receptacle, wait 15 seconds, plug it back in, and verify operation.

9. If the status LED on the keypad controller lights green briefly after power is plugged in but the system does not turn on when OPEN and CLOSE are pressed together, the keypad controller has failed and needs to be replaced.

It powers on, but OPEN and CLOSE do nothing and no flash codes show

1. Check for low voltage and loose connections.

2. Test the remote to verify whether the keypad buttons have failed.

3. Check for loose and corroded connections at the motor terminals, and inspect the wires from the motor to the inner control box in the nose of the trailer.

4. Unplug trailer power from the 2-pole receptacle, wait 15 seconds, plug it back in, and verify operation.

5. If the status LED flashes green continuously and the motor connections have been verified, the motor brushes may be worn and the motor needs to be replaced.

Red flash codes on the keypad controller

Codes flash, pause, and repeat until the problem is corrected. Thunderstone's guide lists no 6-flash code.

"Driver error" is the guide's name for that fault. It has nothing to do with the person driving the truck. For 7 red flashes:

1. Connect an alternate power source to verify a low amperage or voltage problem. The source must be a lead-acid, high-amperage battery, not a charger. Multiple 12-volt batteries wired in parallel are recommended for proper operation.

2. Make sure the battery is fully charged and the charging system on the truck or power supply is running and working properly.

3. Check the connections at the motor for looseness or corrosion.

4. Check the motor wires for cuts, abrasions, or bare spots that may touch ground.

How do I know if the tarp motor is bad?

A tarp motor is the likely problem once you've shown that good power reaches it and it still won't turn. Each system shows that in its own way:

• Roll-Rite: if you had to use the emergency bypass, tell us what happened when you call. The bypass rolls the tarp unless there is a motor issue, so whether the tarp ran on it helps us diagnose what failed.

• Roll-Rite Rite-Touch module: 7 flashes can mean a bad motor, but check the connections and the motor leads first.

• Shur-Co ShurLink EZR: take the motor wire off the In and Out posts and hold OPEN or CLOSE. A reading of at least 12.5 or -12.5 volts across those posts means the solenoid is working. That leaves the motor or a short in the motor wire.

• Shur-Co ShurLink Pro: hold OPEN or CLOSE and check for 12 volts at the motor. If there are 12 volts and the motor does not run, there may be a motor problem.

• Thunderstone Thunder 7000: a status LED that flashes green continuously, with the motor connections verified, means the motor brushes may be worn and the motor needs to be replaced.

How much do electric tarp breakers, relays, solenoids and motors cost?

A circuit breaker costs $18 or $22.80, and a motor costs $1,140 to $1,440. Rule out the low-cost parts before you order a motor. These are our prices as of October 2026.

Electric tarp motors carry the manufacturer's warranty. On the Roll-Rite TarpStretcher motor, that warranty is 5 years.

If the motor is the only part you're replacing, you'll typically buy a motor kit online and install it yourself. The prices in the table are for the motor alone, and a motor kit is a separate product. Our electrical parts are on the electric system parts page.

We pack online orders the same day or the next day, and most U.S. customers receive their package in 3 to 7 days. If you're close enough to drive, you can also buy parts at our parts counter in Teutopolis.

Can I add a manual override to my electric tarp?

You can add a Brumleve manual override to a Roll-Rite electric tarp system on an end dump trailer. There are two kits for it, both designed in-house for Roll-Rite end-dump systems:

• The Brumleve Manual Override Update Kit is $780. It is the flex arm cable assembly, U-joint and splined shaft. Watch the install video.

• The Brumleve Manual Override Complete Rear Arm Kit is $1,560. It has the same parts, plus the mounting brackets, pivot pin, base arm and springs for the rear arm. Watch the install video.

With either kit, the splined shaft is welded to the roll pipe, so the install takes a welder. If you aren't sure which kit your trailer needs, or your system isn't a Roll-Rite end dump, call us.

When should I call a tarp shop?

Call a tarp shop any time the job goes past checking power and connections from the ground. For us, that means:

• You've been through the steps for your system and the tarp still won't run.

• The tests point to the motor, the relay or the solenoid, and you want to confirm the part before you order it.

• Your system isn't a Roll-Rite, a Shur-Co ShurLink or a Thunder 7000, or you can't tell what you have.

• An arm, a spring or the roll pipe is bent, loose or out of place. Stay clear of it.

• The tarp is hung up where you'd have to climb to get at it.

Our number is (217) 857-3777, and we're open Monday through Friday, 7:30 AM to 4:00 PM Central. Have your system brand and model ready, and tell us what you saw: click or no click, and the flash count if there was one. Repairs and installs happen at our shop at 1317 West Main Street, Teutopolis, IL 62467, so plan on bringing the trailer to us. That includes adding a manual override. And if you run another trailer that still has a hand crank, we convert crank systems to electric here too.