Neta U Pro DTC Quick Reference and Low-Voltage Battery Inspection Guide

Fault Background

The Neta U Pro DTC system follows the Neta V's "four-module division" (BMS / VCU / OBC / DCDC), but with more detailed codes: BMS side adds P1B4200 (DC-DC short-to-ground anomaly or manual unplugging during charging), U011600 (communication timeout with VCU—BMS reports a high-level fault but does not receive a power-down command from VCU), P1B4800 (DC charging port over-temperature level 2, poor contact at the charge port), P1B4F00 (pre-charge overcurrent, load operating prematurely or main positive/negative contactor fault), P1B5000 (short circuit during charging); VCU side has P1A5B00 (DCDC charging fault, intermittent connection or burning), P1A5F00 (implausible vehicle speed signal, abnormal ABS wheel speed sensor); OBC side P1D0200/P1D0300 output overvoltage/undervoltage shutdown appear as a pair; DCDC side P1E0100/P1E0200 input undervoltage/overvoltage. The manual states: "The order of listing indicates the priority of faults; check each component in order." Also included is a 12V battery inspection three-method (visual inspection / load test / static voltage test). This article organizes the four DTC tables and battery inspection into a quick reference guide.

DTC Quick Reference (by module)

BMS DTC table:

VCU DTC table: P1A5B00 DCDC charging fault (intermittent connection or burning); high-voltage battery voltage fault (abnormal voltage); ESC system CAN fault (U012387/P1A5F00/P1A7400); P1A5F00 implausible vehicle speed signal (abnormal ABS wheel speed sensor); U007388 VCU CAN network fault; BMS system CAN communication failure fault (open circuit, refer to U011187/P1A7900/P1A7A00).

OBC DTC table: P1D0200 charger output overvoltage shutdown (abnormal voltage from OBC output to battery, refer to P1D0300); P1D0300 charger output undervoltage shutdown (abnormal battery voltage / abnormal connection from OBC output to battery); charger internal serial port fault.

DCDC DTC table: P1E0100 input undervoltage fault (hardware damage); P1E0200 high-voltage DC input overvoltage fault (hardware damage on DCDC high-voltage input side).

Manual statement: The order in the table is the fault priority order; check each component in order; for major faults such as motor smoking or electric leakage, immediately cut off power and report to professional personnel for repair.

12V Battery Inspection Three Methods

Visual inspection (check external condition, situation, and location):

• Battery case damaged → decide whether to replace based on the damage ( case damage can cause acid leakage , use electrolyte diluent or soapy water to treat parts contacted by acid);
• Electrodes (wire terminals) damaged → cannot guarantee good terminal contact, decide whether to replace based on the situation;
• Terminals not correctly connected or tightened → may cause wiring fire and electrical equipment malfunction;
• Battery not properly secured → long-term vibration can damage internal grids and case, shorten lifespan, and pose an explosion risk; tighten fixing bolts to specified torque if necessary.

Load test: Use a digital battery tester with printer; prerequisites: turn off start/stop button and all electrical loads → disconnect battery negative cable → disconnect positive cable.

Static voltage test: Evaluate whether the battery needs charging.

Safety Warnings

• This article is for technical reference only; high-voltage and battery system repairs must be performed by qualified professional technicians (battery expertise + electrician certification + company training authorization) according to OEM specifications; readers without proper knowledge are strictly prohibited from performing operations themselves.
• For major faults such as motor smoking or electric leakage, immediately cut off power and report to professionals; troubleshoot according to the DTC table priority order.
• During battery inspection, first turn off all electrical loads, then disconnect negative, then positive; wear protective equipment when handling acid.
• Tighten battery fixing bolts to specified torque to prevent vibration damage and explosion risk.

Repair Insights

The most memorable DTCs in the Neta U Pro table are three groups of "paired codes": P1D0200/P1D0300 (OBC output overvoltage/undervoltage shutdown) —when they appear as a pair, first check the connection from OBC output to battery and battery voltage, then suspect OBC hardware; P1E0100/P1E0200 (DCDC input undervoltage/overvoltage) —input-side hardware damage is clearly indicated; P1B4F00/P1B5000 (pre-charge overcurrent/short circuit during charging) —the common root cause is "load operating prematurely or main positive/negative contactor fault," don't be misled by the word "short circuit" into checking the wiring harness. Behavior-type codes are also worth remembering: P1B4200 includes "manual unplugging during charging" —such codes are sometimes not faults but operational events. Finally, the manual explicitly states the troubleshooting discipline: DTC table order = priority order , check from top to bottom, don't skip items.

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【This article is for reference only】