iRobot Roomba 690 Troubleshooting

No/incorrect movement

To fix this, remove the wheels and take all of the dirt off them. To remove the wheels, start by flipping the Roomba upside down. There is a wheel located on both sides of the Roomba, and each is held in place by three screws. Take out these screws using a screwdriver, and then you can pull the wheel out.

This wheel encounters debris before the brushes, so this debris often gets lodged in the wheel and around its axle, causing it to not rotate freely. This will prevent the Roomba from moving properly. This issue can be resolved by removing the front caster wheel and cleaning its components. To remove the front caster wheel, start by flipping the Roomba upside down. The front caster wheel is held in by one screw. Remove this screw with a screwdriver and pull the wheel out. The wheel itself is connected to a plastic piece, but the wheel can be pulled out of the plastic piece by using a little force. It will then be easier to clean this wheel and shaft. To put the wheel back, press it back into the plastic piece, and then place it back in the Roomba where it was, and tighten the screw.

One problem that may cause your Roomba to spin in circles is that one of the motors is not working. There is a motor connected to each wheel. To figure out which motor is malfunctioning, it should be the wheel that the Roomba is pivoting around. To get to the motor, start by removing the wheel that the Roomba is pivoting around. The wheel piece should have a few screws that keep the motor closed in. Remove these screws with a screwdriver and open up the compartment with the motor. To put the wheel back, close the compartment with the motor, and tighten the screws. Then put the wheel back in the Roomba and tighten those screws.

Not cleaning properly

To remove the brushes, flip the Roomba upside down, and push down the two yellow tabs that hold the brushes. Then you can remove the brushes by pulling them out. You should clean the dirt and hair out of the brushes, and then inspect them to see if they are worn down. If the brushes are damaged, you should replace them with new ones.

For every Roomba, there will come a point where the filter needs to be emptied so that it can continue to clean properly. For the Roomba 690, the process is rather simple and requires no tools to accomplish, though you may need a replacement filter depending on the condition of the one currently in the Roomba.

To start, flip the Roomba upside down. On the side opposite of the front sensor, you should see a module that is of equal length to the brushes. This is where the filter is stored. To remove the module, apply pressure to slide it horizontally away from the Roomba. It should slide out. Next, looking at the surface of the module that was facing towards the brushes, you should see the filter within the module. Use the yellow tab to open up the module latch holding the filter. After this, the filter can be slid out. Empty and clean the filter, and then replace. In the case where the filter is very dirty or unusable, you should replace the filter with a new one. To put the filter module back in place, simply reverse this process.

Roomba not receiving power

Before going to replace the battery see if it is the charger that is the problem. Plug the docking port into an outlet. If the light on the docking port doesn’t illuminate, try using a different outlet to ensure that the outlet itself is not at fault. If the docking port does not have power after trying this, your charging cord probably needs to be replaced.

Dust picked up from the Roomba while cleaning can obstruct the Roomba from properly docking to charge. Double check to ensure that both the Roomba and the port are clean.

Replacing the battery is quite simple for the Roomba 690. First, flip the Roomba over so the wheels are facing upward. You should spot four screws holding the bottom cover in place. Looking at the Roomba from the back, two should be located below the driving wheels and the other two are toward the front of the wheels closer to the center and in between the driving wheels and steering wheel. Unscrew these and remove the cover. Once the plate is removed you should see the battery located roughly in the center of the Roomba. No unscrewing is required here, simply use the tags on each end of the battery to pull it out. To put the new battery in, simply slide it into place where the original was and replace the plate and tighten the screws. The battery should only be able to fit in the correct orientation.

Battery overheating

Sometimes when the Roomba will not charge due to an overheating battery. A possible reason the battery overheats is because it is a fake Roomba battery, but sometimes it is just because it needs to cool down. Give the battery about three hours to cool down and attempt to charge it again. If this issue continues to persist, it may be due to a faulty battery. In this case, the battery will need to be replaced. See the above section for "Roomba not charging" under the "Faulty battery" subheading.

Not running on black/dark carpet

On the bottom of the Roomba there will be a number of sensors around the edge which are used to tell if the Roomba is approaching an edge such as a flight of stairs, and are thus titled cliff sensors. They work by having an infrared light bounce off the ground and then be detected by the sensor, when the light is not detected the Roomba will stop.

This solution is not perfect as it will require upkeep, although if it is done well you may go some time without needing to redo it. The solution is to cover the sensors with a reflective surface so the light is able to be detected and wont be obfuscated by the carpet.

First, take a sheet of paper and cover it in glossy tape, clear packing tape works well. Next, locate the six cliff sensors around the bottom edge of the Roomba, they should be in pairs, one on either side of either wheel, and cut the paper a little bit larger than the sensors. Finally, take the tape and secure the paper over the sensors, being careful to not impede the ability of the wheels or the yellow sweep arm.

This can solve the problem, however, will cause another issue for users vacuuming at the top of steps as the sensors will no longer be able to detect edges. As a result, you may have to purchase the Roomba sensor barriers or conversely place a gate or some other block before the stairs.

In some cases the simple method may not work, however, there is a guaranteed, but also more involved method of fixing the issue. It involves almost a complete tear down and many tools, however, it will fix the issue in a cleaner way with no upkeep required, unless you want to undo the modification.

First, flip the Roomba so that the wheels are in the air and remove all of the screws on the bottom, including the screw securing the yellow brush.  Once this is done you will have access to the first layer of the internals including the battery, which should be removed immediately. Now, on the side of the Roomba, locate the bumper. When found locate and unscrew the ten screws on the bottom which are securing the bumper to the body. This will free the bumper, however, the bumper sensor will still be connected to the circuit board with a wire so be careful to not break it.  Next, you have to disconnect that wire and to do so we must remove the circuit board.

Flip the Roomba over so that it is upright. Find the cutout within the silver ring, this is a handle that you can use to easily remove the top plastic cover. Once removed, there will be six screws on the newly exposed surface that must be removed in order to remove the majority of the housing.  With this layer off you can remove the center display housing, the top three layers can just be removed, however, the bottommost layer requires a screwdriver. Once removed you can now remove the clear plastic cover protecting the circuit board.

You can now begin unscrewing the circuit board being very careful to avoid damaging the board as you may have to replace it or resolder anything broken.  While the board is unscrewed, unplug all of the wires on the top side being careful to not break the clips that attach them to the board.  Now gently wiggle the board while pulling up to lift it off of the studs.  With the board loose locate the wire that connects to the bumper sensor and disconnect it.  This completely frees the bumper and it can be placed off to the side.  With the bumper removed you will have access to the proximity sensors, which appear as a half circle plastic band under the bumper, and they can just be moved out of the way, without tools, as they are directly over the cliff sensors.

The cliff sensors are directly on the perimeter of the circle and appear as a rectangular module slotted on the edge of the body. Using a thin, metal object slide it between the sensor and the body and twist while pushing up with your other hand causing the whole module to pop out. Once out locate the clips on the side of the module and using the same metal object, pry the clips open giving you access to the sensors themselves. Split the black casing and you will see two small bulbs: a light, transmitter, and dark, receiver.  Simply place the bulbs next to each other in the same direction and tape them together.  Then just reassemble the sensor module.  You need to repeat this for all of the cliff sensors on the Roomba in order to solve the issue.

Once all of the sensors are modified simply put everything back together the same way you took it apart.