P157016 - P157016 AC Side Voltage Low
Fault Depth Definition
Fault code P157016 (Low AC-Side Voltage) is part of the key input protection logic of the On-Board Charger (On-Board Charger, OBC), aimed at monitoring power quality in the high-voltage energy management chain. In the vehicle architecture, this control unit is responsible for collecting real-time AC parameters from the external grid, ensuring that the AC-side voltage at the input end is within a safe and effective operating range before entering the on-board charger for rectification and energy conversion. This state belongs to the active health management mechanism of the whole-vehicle charging system; once the voltage signal is detected below the preset physical threshold of the system, a protective fault mark is triggered to prevent low-voltage conditions from damaging the high-voltage battery pack or causing subsequent power electronic component overload risks.
Common Failure Symptoms
After fault code P157016 is written, the vehicle will exhibit the following characteristics at the driving and charging interaction levels:
- Charging Function Blocking: The vehicle is completely unable to initiate an AC charging process; after plugging the gun into a charging device, the on-board system refuses the handshake and prohibits the charging path.
- Instrument Display Abnormality: The driver's instrument panel or center control display will light up the high-voltage fault warning light and explicitly prompt "Do Not Use" or display the corresponding Diagnostic Trouble Code (DTC) P157016.
- Charging Process Interruption: If the fault occurs during charging, the system will forcibly cut off power transmission, causing the battery to fail to gain energy and immediately terminating the current charging session.
Core Failure Cause Analysis
Based on existing data and technical logic, this fault may involve anomalies in three dimensions: external energy links, physical connections, and internal control units. Specific cause categories are as follows:
- Hardware Component Faults: Mainly includes damage to or unstable output of the power module of external AC charging equipment (charging piles); aging of input detection circuits inside the On-Board Charger (OBC) or high-voltage components experiencing leakage phenomena, leading to distorted voltage signal collection.
- Circuit and Connector Connections: High-voltage wires in the vehicle wiring harness used for monitoring AC-side voltage have insulation damage, loose pins, or oxidation/corrosion on contact surfaces, introducing additional contact resistance causing low terminal sampling voltage values.
- Controller Logic Calculation: The sampling accuracy of the internal ADC (Analog-to-Digital Converter) inside the on-board charger control unit drifts, or protection algorithm voltage determination thresholds have abnormal configurations, leading the system to misjudge normal fluctuation range voltages as being below the prescribed range.
Technical Monitoring and Trigger Logic
The system's fault judgment follows specific electrical characteristic monitoring rules. Specific technical parameters and trigger conditions are as follows:
- Monitoring Target: The system primarily monitors the real-time voltage amplitude of the AC input bus (AC Input Bus), focusing on tracking the stability of the energy conversion entry signal before the drive motor.
- Numerical Judgment Range: Set fault condition to AC voltage less than specified threshold, i.e., system logic enters fault state when $U_{AC} < V_{threshold}$. Here $V_{threshold}$ refers to the minimum allowable input voltage lower limit set inside the control unit, which is usually fixed in calibration data.
- Trigger Conditions: Vehicle is in a dynamic monitoring process of conducting AC charging (i.e., running stage after charging gun connection and successful handshake). Once continuous or instantaneous voltage below preset value $V_{threshold}$ is detected within sampling frequency, the control unit will lock the fault condition and generate P157016 fault code, while executing corresponding protection strategies to terminate energy transmission.
Cause Analysis Based on existing data and technical logic, this fault may involve anomalies in three dimensions: external energy links, physical connections, and internal control units. Specific cause categories are as follows:
- Hardware Component Faults: Mainly includes damage to or unstable output of the power module of external AC charging equipment (charging piles); aging of input detection circuits inside the On-Board Charger (OBC) or high-voltage components experiencing leakage phenomena, leading to distorted voltage signal collection.
- Circuit and Connector Connections: High-voltage wires in the vehicle wiring harness used for monitoring AC-side voltage have insulation damage, loose pins, or oxidation/corrosion on contact surfaces, introducing additional contact resistance causing low terminal sampling voltage values.
- Controller Logic Calculation: The sampling accuracy of the internal ADC (Analog-to-Digital Converter) inside the on-board charger control unit drifts, or protection algorithm voltage determination thresholds have abnormal configurations, leading the system to misjudge normal fluctuation range voltages as being below the prescribed range.
Technical Monitoring and Trigger Logic
The system's fault judgment follows specific electrical characteristic monitoring rules. Specific technical parameters and trigger conditions are as follows:
- Monitoring Target: The system primarily monitors the real-time voltage amplitude of the AC input bus (AC Input Bus), focusing on tracking the stability of the energy conversion entry signal before the drive motor.
- Numerical Judgment Range: Set fault condition to AC voltage less than specified threshold, i.e., system logic enters fault state when $U_{AC} < V_{threshold}$. Here $V_{threshold}$ refers to the minimum allowable input voltage lower limit set inside the control unit, which is usually fixed in calibration data.
- Trigger Conditions: Vehicle is in a dynamic monitoring process of conducting AC charging (i.e., running stage after charging gun connection and successful handshake). Once continuous or instantaneous voltage below preset value $V_{threshold}$ is detected within sampling frequency, the control unit will lock the fault condition and generate P157016 fault code, while executing corresponding protection strategies to terminate energy transmission.
Diagnostic Trouble Code (DTC) P157016.
- Charging Process Interruption: If the fault occurs during charging, the system will forcibly cut off power transmission, causing the battery to fail to gain energy and immediately terminating the current charging session.
Core Failure Cause Analysis
Based on existing data and technical logic, this fault may involve anomalies in three dimensions: external energy links, physical connections, and internal control units. Specific cause categories are as follows:
- Hardware Component Faults: Mainly includes damage to or unstable output of the power module of external AC charging equipment (charging piles); aging of input detection circuits inside the On-Board Charger (OBC) or high-voltage components experiencing leakage phenomena, leading to distorted voltage signal collection.
- Circuit and Connector Connections: High-voltage wires in the vehicle wiring harness used for monitoring AC-side voltage have insulation damage, loose pins, or oxidation/corrosion on contact surfaces, introducing additional contact resistance causing low terminal sampling voltage values.
- Controller Logic Calculation: The sampling accuracy of the internal ADC (Analog-to-Digital Converter) inside the on-board charger control unit drifts, or protection algorithm voltage determination thresholds have abnormal configurations, leading the system to misjudge normal fluctuation range voltages as being below the prescribed range.
Technical Monitoring and Trigger Logic
The system's fault judgment follows specific electrical characteristic monitoring rules. Specific technical parameters and trigger conditions are as follows:
- Monitoring Target: The system primarily monitors the real-time voltage amplitude of the AC input bus (AC Input Bus), focusing on tracking the stability of the energy conversion entry signal before the drive motor.
- Numerical Judgment Range: Set fault condition to AC voltage less than specified threshold, i.e., system logic enters fault state when $U_{AC} < V_{threshold}$. Here $V_{threshold}$ refers to the minimum allowable input voltage lower limit set inside the control unit, which is usually fixed in calibration data.
- Trigger Conditions: Vehicle is in a dynamic monitoring process of conducting AC charging (i.e., running stage after charging gun connection and successful handshake). Once continuous or instantaneous voltage below preset value $V_{threshold}$ is detected within sampling frequency, the control unit will lock the fault condition and generate P157016 fault code, while executing corresponding protection strategies to terminate energy transmission.