For this repair, you will need a Phillips head screwdriver and a replacement mainboard.
Make sure Bob’s side power switch is turned OFF and flip him over onto a flat surface. Remove the screw securing Bob’s main brush in place.
Remove Bob’s main brush to access and remove the screw located beneath it (depending on Bob's model, there may be 2 screws).
Remove the 5 screws lining Bob’s underside.
Flip Bob back onto his wheels and lift his cover up. To remove Bob’s cover completely, you must detach 3 circuit plugs from his mainboard. Pinch the small white tab on the side of each circuit plug and pull upwards to remove it.
Slide Bob’s power inlet out and place his cover aside.
To remove the mainboard, you will need to detach all of the remaining circuit plugs. Remember where each plug belongs, as you will need to reattach them to the replacement mainboard later.
Next, remove the 3 screws securing the mainboard in place.
Lift the old mainboard out and place the new mainboard in its stead.
Make sure the replacement mainboard lies flat over the empty screw posts and replace the 3 screws.
You may now begin reconnecting all of the mainboard's circuit plugs.
Left edge of the mainboard:
The small circuit plug with yellow and black wires attaches to the top of the mainboard’s left edge.
3 circuit plugs attach below the previous plug in the following order: a medium-sized plug with two pairs of twisted wires, one red and white, the other pink and black; a wide circuit plug with multicolored wires; and a small circuit plug with blue and black twisted wires (shown empty).
Bottom edge of the mainboard:
The wide circuit plug with multicolored wires — the plug for Bob’s right wheel — attaches to the far right of the mainboard’s bottom edge.
3 circuit plugs attach the left of the previous plug in the following order: a small plug with orange and black wires; a small plug with yellow wires; a medium-sized plug with red, brown, black, and white wires.
Leave the remaining 3 spaces on the bottom edge empty.
Right edge of the mainboard:
The circuit plug with the orange and black wires — the plug for Bob’s power inlet — attaches to the bottom of the mainboard's right edge.
The wide circuit plug with the red, black, and blue wires attaches above the previous plug.
Top edge of the mainboard:
2 wide circuit plugs attach to the mainboard’s top edge. Plug in the one on the left; leave the one on the right empty.
Now you’re ready to put Bob’s cover back together. First, reattach all the circuit plugs you removed to separate Bob's cover. Press down on each circuit plug to ensure it securely locks in place.
Before closing Bob's cover, slide his power inlet back in its place.
Carefully realign the edges of Bob’s cover and flip him onto his back. Replace the 5 screws on his underside to seal his cover together.
Replace the 1 or 2 screws located beneath Bob's main brush.
Place the main brush back in its compartment. Attach the end piece first
and align the square end with the square-shaped notch inside Bob.
Lastly, replace the screw securing Bob's main brush in place and your repair is complete!