P04AC – BMW DTC

BMW DTC P04AC – EVAP System Purge Control Valve ‘B’ Circuit Low

DTC P04AC meaning on BMW

The Diagnostic Trouble Code (DTC) P04AC for BMW refers to an issue with the EVAP (Evaporative Emission Control System) System Purge Control Valve ‘B’ Circuit registering a low voltage condition.

BMW DTC P04AC symptoms

Symptoms of the DTC P04AC on a BMW may include:

  • Check Engine Light (MIL) illuminated on the dashboard
  • Decreased fuel efficiency
  • Engine may run rough or stall

BMW DTC P04AC causes

Common causes of the DTC P04AC on a BMW include:

  • Faulty EVAP System Purge Control Valve ‘B’
  • Wiring or connector issues in the circuit
  • ECU (Engine Control Unit) malfunction

BMW DTC P04AC seriousness

While the DTC P04AC may not cause immediate drivability issues, it is important to address it promptly to prevent potential damage to the vehicle’s emission control system and ensure optimal performance.

How to diagnose DTC P04AC on BMW

To diagnose the DTC P04AC on a BMW, a mechanic may perform the following steps:

  1. Use a diagnostic scanner to retrieve the fault code and freeze frame data
  2. Inspect the EVAP System Purge Control Valve ‘B’ and associated wiring for any visible damage
  3. Test the purge control valve for proper operation
  4. Check the ECU for any stored codes or issues

How to fix DTC P04AC on BMW

To fix the DTC P04AC on a BMW, the following steps may be taken:

  1. Replace the faulty EVAP System Purge Control Valve ‘B’
  2. Repair or replace any damaged wiring or connectors in the circuit
  3. If necessary, address any ECU issues or malfunctions

How to erase DTC P04AC on BMW

After addressing the underlying issue causing the DTC P04AC on a BMW, the fault code can be erased using a diagnostic scanner capable of clearing codes. Once the code is cleared, the Check Engine Light should turn off.

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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