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OBD-II code family

Cooling Fan Control and Speed Faults (15 codes)

15 related fault descriptions. Use each full code and the exact vehicle service information to identify its circuit, monitored condition, and required tests.

What these codes mean

P0480, P0481 and P0482 identify numbered fan-control circuits. P0691/P0692 add low/high control results for circuit 1, P0693/P0694 for circuit 2 and P0695/P0696 for circuit 3. P0483 concerns rationality, P0484 overcurrent and P0485 power/ground. P0493 names overspeed, while P0494/P0495 distinguish low/high fan speed. A control-circuit high result and a high-speed result are different conditions; keep each exact code when choosing a test.

Circuit 1, 2 or 3 does not establish the number of motors, relays or speed stages. Identify the installed electric-fan, fan-clutch and controller arrangement, full code and required command state. Fan noise, visible movement and a scan-tool speed are different observations; the feedback itself can need validation.

Audi’s September 2024 bulletin 19-24-67 uses supply and PWM checks for its listed 2021–2024 applications with P048000/P048100. Ford SSM 47999 covers specified 2016–2019 6.7L F-Super Duty/F650–750 vehicles with a fan that stays on or is inoperative, including P0480/P0494/P0495. It directs an updated diagnostic path to avoid unnecessary clutch replacement. Neither example makes these codes exclusively electric or mechanical.

The low/high control examples also depend on the installed monitor. Mitsubishi’s cited 2022 PHEV-ECU information compares commanded and observed radiator/condenser relay states for P0691–P0694. Ford’s covered 2023–2024 diesel summary allows an open or a short to ground for P0693 and a short to power for P0694. Use the required command state and actual circuit diagram; a generic high/open or low/ground translation is not sufficient.

On the cited 2009 Durango 2WD 5.7L Hybrid, the HGM monitors the N27 fan-3 control circuit: P0695 detects short to ground and P0696 short to voltage under their specified conditions. The low-code procedure also considers open wiring and a stalled/obstructed fan. These are bounded application examples, not evidence of three relays, a universal third high-speed stage or a socket that must be replaced. The hybrid procedure requires its high-voltage precautions before work near high-voltage components.

Save the scan, actual temperature warnings and operating history. Inspect only accessible cooled connections after the required isolation. A key removed from the vehicle does not by itself establish safe fan access. Do not stop, spin or load a fan by hand, bridge a relay, feed an unidentified controller directly or reproduce an overheating condition on the road.

Have the specified supply, return, control, speed-feedback and component checks performed. An overcurrent result does not alone prove a binding motor or successful protective shutdown; low/high speed does not establish which part failed. Repair the demonstrated condition and verify the relevant control and monitor. Follow the vehicle’s overheating instructions and obtain an itemized quote for the confirmed job.

Identify the circuit on your vehicle

Match the full DTC, reporting module, and any failure-type suffix to the service information for your exact year, make, model, engine, and equipment. An identifier alone does not establish installed hardware count, location, connector pinout, or a universal measurement.

Where the manufacturer publishes its own meaning for this code, that is the one to work from — it describes the actual component on your vehicle, which the generic definition cannot. Keep the generic description for what it is good for: it tells you which subject area the standard assigned the code to, which is useful context when the two appear to disagree. If they do disagree, follow the manufacturer.

Editorial context

About This Diagnostic Information

These guides provide general diagnostic context. A trouble code records a condition detected by a control module. It does not automatically identify a failed part, and the right diagnostic procedure can vary by vehicle.

References for this guide

  • SAE J2012, April 2002

    Referenced by P0480, P0481, P0482, P0483, P0484, P0485, P0493, P0494, P0495, P0691, P0692, P0693, P0694, P0695, P0696. P0480, P0481, P0482, P0483, P0484, P0485, P0493, P0494, P0495: Historical Table B5, PDF 18, distinguishes fan control and speed, EGR, secondary-air bank and EVAP flow/circuit conditions. It does not specify installed hardware or diagnostic tests. P0691, P0692, P0693, P0694, P0695, P0696: Historical Table B7, physical PDF 22, separates cylinder, glow-module communication, relay control/sense, fan and reference-voltage conditions. Table B8 on the same page names P0700 as a transmission MIL request. Vehicle service information defines the installed monitor and procedure.

  • Audi 19 24 67 / 2075348, September 2024

    Referenced by P0480, P0481. P0480, P0481: Listed 2021–2024 applications with P048000/P048100 and continuous fan operation: supply and PWM-wiring checks precede Guided Fault Finding. This is not a universal relay or fan-replacement instruction.

  • Ford SSM 47999, 2019

    Referenced by P0480, P0494, P0495. P0480, P0494, P0495: Some 2016–2019 F-Super Duty/F650–750 6.7L applications: the listed fan codes require the applicable diagnostic path to prevent unnecessary fan-clutch replacement.

  • RepairPal check engine light diagnosis and testing estimate

    Referenced by P0480. P0480: National diagnostic-service example, updated September 3, 2026 and checked November 6. Repair, special access and additional testing are separate.

  • Mitsubishi 2022 PHEV-ECU — P0691–P0694 service information

    Referenced by P0691, P0692, P0693, P0694. P0691, P0692, P0693, P0694: The 2022 PHEV service information describes PHEV-ECU radiator/condenser relay monitoring for P0691–P0694. Commanded and observed states are compared, with harness, connector, relay, fusible-link and controller checks. Fan numbering and these relay roles must be matched to the actual vehicle.

  • Ford 2023–2024 diesel OBD operation summary

    Referenced by P0693, P0694. P0693, P0694: Physical PDF 117 describes the covered secondary electric-fan relay: P0693 can detect an open or a short to ground; P0694 detects a short to power. PDF 118 separately lists P0685 main-relay control/open. Covered Ford configurations require their own circuit diagnosis.

  • Dodge Durango 2009 2WD 5.7L Hybrid — P0695 service chart

    Referenced by P0695. P0695: Archived 2009 Durango 2WD 5.7L Hybrid chart: the HGM detects an N27 fan-3 control short to ground. Its diagnosis also considers an open circuit, a stalled or obstructed fan, fan hardware and the HGM. The chart requires high-voltage safety procedures before work near high-voltage components.

  • Dodge Durango 2009 2WD 5.7L Hybrid — P0696 service chart

    Referenced by P0696. P0696: Archived 2009 Durango 2WD 5.7L Hybrid chart: with fan control requested, the HGM detects an N27 fan-3 control short to voltage. The procedure considers wiring, fan hardware and HGM faults and requires the applicable high-voltage precautions. It does not define every vehicle’s fan-3 design.

Manufacturer service information, technical service bulletins, wiring diagrams, and vehicle-specific procedures should take precedence when available.

AutoLogicTools was founded by Vincent Fisk, an automotive locksmith and shop owner in San Diego with hands-on experience in vehicle keys, immobilizer systems, electrical issues, modules, programming, and diagnostics.