BMW DTC P1046 – Internal VVL-Control Module Read Only Memory (ROM) Error (Bank 2)
DTC P1046 meaning on BMW
DTC P1046 on a BMW indicates an Internal Variable Valve Lift-Control Module Read Only Memory (ROM) Error in Bank 2. This fault code is related to the engine’s Variable Valve Lift (VVL) system, which controls the opening and closing of the engine’s intake and exhaust valves for optimal performance.
BMW DTC P1046 symptoms
Symptoms of DTC P1046 in a BMW may include engine misfires, rough idling, reduced engine performance, decreased fuel efficiency, and in some cases, the vehicle may go into a limp mode where power is limited to prevent further damage.
BMW DTC P1046 causes
The most common causes of DTC P1046 in a BMW are a faulty VVL control module, damaged wiring or connectors in the VVL system, or a corrupted ROM within the VVL control module.
BMW DTC P1046 seriousness
DTC P1046 should be addressed promptly as it can lead to engine performance issues and potential long-term damage if left unresolved. Ignoring this fault code may result in further complications and increased repair costs.
How to diagnose DTC P1046 on BMW
To diagnose DTC P1046 on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the fault code and perform a thorough inspection of the VVL control module, wiring, and connectors. They may also conduct tests to check the functionality of the VVL system components.
How to fix DTC P1046 on BMW
Fixing DTC P1046 on a BMW usually involves replacing the faulty VVL control module, repairing any damaged wiring or connectors, and reprogramming the ROM within the VVL control module if necessary. It is recommended to follow the manufacturer’s repair procedures and use genuine BMW parts for a reliable repair.
How to erase DTC P1046 on BMW
Once the underlying issue causing DTC P1046 on a BMW has been fixed, the fault code can be erased using a diagnostic scanner. By clearing the fault code, the vehicle’s ECU will no longer register the error, provided the repair was successful.
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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