Cooling Fan
P1900 — Cooling Fan
System: Powertrain | Type: Manufacturer-Specific | Make: Infiniti
P1900 is a manufacturer-specific powertrain diagnostic trouble code recorded for Infiniti vehicles. 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.
P1900 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.
This code is triggered when the Engine Control Module (ECM) detects an issue with the cooling fan control circuit or its operation. The ECM monitors the cooling fan relay, fan motor speed, and electrical circuit integrity. If the fan does not operate as commanded or if there is an electrical fault, the ECM sets this code.
Detailed possible causes for P1900 are available to TaT members.
Unlock with Free TrialStep-by-step diagnostic guidance for P1900 is available to TaT members. Our Diagnostic Assistant provides professional-level troubleshooting procedures written by experienced technicians.
Unlock with Free Trial| Code | P1900 |
| System | Powertrain |
| Type | Manufacturer-Specific |
| Make | Infiniti |
| Causes | Available |
| Diag. Assistant | Available |
| Video | — |
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