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C0404 BMW Fault Code

Check C0404 OBD Fault Code Reason
Description:

Engine Coolant Temperature (ECT) Circuit High Input Indicates the sensor signal is greater than Self-Test maximum. The ECT sensor maximum is 4.6 volts or -50 C (-58 F). Note on some vehicles that are not equipped with an ECT sensor, CHT can be used and can set this DTC. Open circuit in harness Sensor signal short to power Damaged PCM Improper harness connection Damaged sensor ECT V PID reading greater than 4.6 volts with key ON and engine OFF or during any engine operating mode indicates a hard fault.

C0404 Code Symptoms :

See C0404 in engine

There are currently two main types of cylinder deactivation used today, depending on the type of engine. C0404 code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Diagnosis And Repairing C0404

C0404 OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.

How to fix C0404 code ?

See C0404 repair manual
  • Camshaft advance mechanism binding (VCT unit)
  • Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection
  • Damaged VCT phaser
  • Open circuits caused by damage to wiring.

BMW Cars that meet C0404 error