Cooling fan over speed (clutch locked)
P0493 — Cooling fan over speed (clutch locked)
System: Powertrain | Type: Generic (OBD-II Standard) | Make: Generic
P0493 is a generic (obd-ii standard) powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.
Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.
Because P0493 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.
The Powertrain Control Module (PCM) sets this code when it detects that the cooling fan is operating at a higher speed than commanded, which may indicate a locked-up fan clutch or an electrical issue. An over-speeding fan can lead to excessive noise, reduced fuel efficiency, and potential cooling system damage.
Detailed possible causes for P0493 are available to TaT members.
Unlock with Free TrialStep-by-step diagnostic guidance for P0493 is available to TaT members. Our Diagnostic Assistant provides professional-level troubleshooting procedures written by experienced technicians.
Unlock with Free Trial| Code | P0493 |
| System | Powertrain |
| Type | Generic (OBD-II Standard) |
| Make | Generic |
| Causes | Available |
| Diag. Assistant | Available |
| Video | — |
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