BMW DTC P164A – Main Relay Undervoltage
DTC P164A meaning on BMW
DTC P164A on a BMW indicates a Main Relay Undervoltage fault. This fault code is triggered when the power supply voltage to the main relay falls below the specified threshold, causing issues with the relay’s operation.
BMW DTC P164A symptoms
Symptoms of a DTC P164A on a BMW may include difficulty starting the vehicle, intermittent stalling, or the engine not running smoothly. In some cases, the vehicle may go into a limp mode or fail to start altogether.
BMW DTC P164A causes
The main causes of a DTC P164A on a BMW can include a faulty main relay, poor electrical connections, a weak battery, or issues with the vehicle’s charging system. It is essential to inspect these components thoroughly to determine the root cause of the fault.
BMW DTC P164A seriousness
While a DTC P164A may not always result in immediate danger, it can lead to significant inconvenience and potential safety issues if the vehicle fails to start or stalls unexpectedly. It is crucial to address this fault promptly to avoid being stranded or causing further damage to the vehicle.
How to diagnose DTC P164A on BMW
To diagnose a DTC P164A on a BMW, a diagnostic scan tool capable of reading fault codes is required. The technician should check the main relay’s voltage supply, inspect the relay for any signs of damage, and test the vehicle’s battery and charging system to ensure they are functioning correctly.
How to fix DTC P164A on BMW
Fixing a DTC P164A on a BMW typically involves replacing the faulty main relay, addressing any poor electrical connections, ensuring the battery is in good condition, and verifying the charging system’s proper operation. It is recommended to follow the manufacturer’s repair procedures and use quality replacement parts.
How to erase DTC P164A on BMW
After fixing the underlying issue causing the DTC P164A fault code on a BMW, the code can be erased using a diagnostic scan tool. The technician should clear the code from the vehicle’s memory to reset the system and ensure the fault has been successfully addressed.
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
Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.