# Inspection

With the robot switched off and the supply unplugged:

- **Belts** (joints 1, 3, 4, 5): press each with a finger through its cover opening; it should give a little and
  spring back. A belt that sags or that you can push against the pulley needs tensioning ([Belts](https://docs.source-robotics.com/PAROL-docs/1.1/07-maintenance/belts/)).
  Look for frayed edges and missing teeth.
- **Couplers and set screws**: hold the output of each joint and try to turn the motor side; any play that is not
  the gearbox's backlash is a loose set screw ([Couplers and threadlocker](https://docs.source-robotics.com/PAROL-docs/1.1/07-maintenance/couplers/)).
- **Limit switches and sensors**: press each switch lever; it should click. The inductive sensors' LEDs light
  when a screw head comes near.
- **Printed parts**: cracks at screw bosses and bearing seats, especially on the elbow and the upper arm, and
  any warping of the forearm from heat.
- **Cables and tubes**: chafing where the arm's cables pass through the joints, and where the gripper's cable
  and tubes cross joints 5 and 6 from the forearm; the gripper cable's connector tight.
- **The fan**: turning when the robot is on, and the intake free of dust. A stopped fan overheats the drivers.
- **The base**: the mounting bolts tight, the E-stop button firm in its housing.

Then switch on, home, and watch the homing: each joint should back off and re-approach its switch cleanly, and
the pose at the end should match the witness marks ([Checking the homing](https://docs.source-robotics.com/PAROL-docs/1.1/07-maintenance/homing-check/)).

## Cleaning

Clean the robot switched off and unplugged. Wipe the printed parts with a dry or slightly damp cloth, or with a little
isopropyl alcohol on the cloth for grease; use no other solvents on them, and never spray anything into the base, where the control board and the fan are open to it.
Clear dust from the fan intake with a soft brush or a vacuum cleaner, not with compressed air, which drives the
dust into the board.