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Home DTC Codes P0665 Medium · 30-60min
P0665 Critical

OBD2 code P0665: Engine computer - Internal error

Internal engine computer error.

ECU: ECM

Detected Root Component

Powertrain Component

Confidence level: low

Observed Symptoms

  • Engine light on (MIL/Check Engine)
  • Unable to start
  • Dashboard errors

Possible Causes

  • Faulty engine computer (ECU)
  • Discharged or defective battery
  • Alternator not charging
  • Damaged wiring
Diagnostic Progress 0 %
Difficulty Medium
Est. time 30-60min
Tools Required 5 tool(s)

Tools Required

multimeter OBD scanner wiring diagram test light fuse puller

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Diagnostic Result

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Parts likely to be the cause (Moteur (général))

Moteur (général)

Moteur (général)

Photo d'illustration : Moteur (général)

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Frequently asked questions about code P0665

What does code P0665 mean?

OBD2 code P0665: Engine computer - Internal error. Internal engine computer error.

What are the symptoms of code P0665?

Code P0665 may cause: Engine light on (MIL/Check Engine), Unable to start, Dashboard errors. The intensity of these symptoms varies depending on the vehicle and driving conditions.

What causes code P0665?

The most common causes of code P0665 are: Faulty engine computer (ECU), Discharged or defective battery, Alternator not charging, Damaged wiring. A proper OBD2 diagnostic will pinpoint the exact cause.

Is it serious to drive with code P0665?

Yes, code P0665 is critical (Critical). Avoid driving and consult a professional promptly to prevent major damage.

How do I fix code P0665?

Start by reading the code with an OBD2 scanner, then follow the interactive decision tree on this page. Priority causes to check: Faulty engine computer (ECU), Discharged or defective battery, Alternator not charging, Damaged wiring. Difficulty: Medium · Estimated time: 30-60min.