P0066 – BMW DTC

BMW DTC P0066 – Air Assisted Injector Control Circuit or Circuit Low

DTC P0066 meaning on BMW

DTC P0066 on a BMW refers to the Air Assisted Injector Control Circuit or Circuit Low. This diagnostic trouble code indicates that there is an issue with the control circuit of the air assisted injector system, specifically that the circuit voltage is lower than the specified range.

BMW DTC P0066 symptoms

Symptoms of DTC P0066 on a BMW may include:

  • Check Engine Light illuminated on the dashboard
  • Decreased engine performance
  • Engine misfires
  • Reduced fuel efficiency

BMW DTC P0066 causes

Common causes of DTC P0066 on a BMW include:

  • Faulty air assisted injector
  • Wiring or connector issues in the control circuit
  • ECU (Engine Control Unit) malfunction

BMW DTC P0066 seriousness

DTC P0066 should not be ignored as it can lead to poor engine performance and reduced fuel efficiency. Continuing to drive with this fault may cause further damage to the engine components.

How to diagnose DTC P0066 on BMW

To diagnose DTC P0066 on a BMW, a mechanic would typically:

  • Use a diagnostic scanner to retrieve the fault code and related data
  • Inspect the air assisted injector and its wiring for any visible damage
  • Check the ECU for any stored fault codes or issues

How to fix DTC P0066 on BMW

To fix DTC P0066 on a BMW, the following steps may be taken:

  • Replace the faulty air assisted injector
  • Repair or replace any damaged wiring or connectors in the control circuit
  • If necessary, reprogram or replace the ECU

How to erase DTC P0066 on BMW

To erase DTC P0066 on a BMW, the fault code can be cleared using a diagnostic scanner. After the repair has been completed, the code can be cleared to reset the Check Engine Light and ensure that the issue has been resolved.

Recommended tools & DTC Scanners for BMW

Best Diagnostic App for modern BMWs: BimmerLink

Recommended Bluetooth adapter for Bimmerlink: OBDLink CX

Cable adapter for Bimmerlink: Enet Cable USB Type C

For older BMWs we recommend: Autel AutoLink AL319 (2024 version)

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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