4148

Common Causes

• Fan breakdown: the fan motor itself has failed
• Fan stuff: chips, dust or swarf packed around the blades stopping rotation
• Fan power connector loose, burnt or disconnected
• Broken wiring between the fan power connector and the fan

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = Fixed code: the power supply unit external cooling fan has stopped.
2. 2Locate the external cooling fan on the power supply unit for the axis or spindle named in the object and check for fan stuff such as chips or dust jamming the blades; clean the blockage out.
3. 3With power locked out, inspect the fan power connector listed among the probable faulty locations for loose or burnt pins; a poor connector contact is a common cause of this fixed code 1 alarm.
4. 4Spin the fan blades by hand to feel for bearing stiffness; stiffness with no stuff present points to fan breakdown, one of the probable faulty locations for the named axis or spindle.
5. 5Restore power and watch the fan at start-up: a fan that hums but does not turn has suffered fan breakdown, while a dead fan with a good connector needs voltage measured at the fan power connector.
6. 6If the object shows none (spindle) rather than an axis name, confirm which power supply unit fan stopped before ordering parts; replace the failed fan or repair its connector and wiring, then clear the fixed code 1 condition by restoring fan rotation.