DTC P0AA1 - Precharge Circuit Malfunction. Product Family. Fault Supported. Earliest Firmware Supported. Orion BMS [Original] (24 - 180 Cell). NO. N/A. Orion BMS 2 (24 - 180 Cell). YES. v3.6.2. Orion JR [Original] (16 Cell). NO. N/A. Orion JR 2 (16 C

DTC P0AA1 = Precharge Circuit Malfunction

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EVolve Electrics

Precharge Circuit

No cell voltages appear (Orion Jr. BMS)

Problems connecting to the Orion Jr. BMS unit via PC software

No cell voltages are showing in the utility

Not all cell voltages appear in live cell data

Error output is on, but no error codes are present

Problems connecting to the Orion BMS unit via PC software

Problems Viewing Data in Utility

Viewing CANBUS Communication Matrix

Diagnosing CANBUS Communication Problems

Problems With CANbus

Cells are not balancing, but should be

Replacing one or more cells

Internal resistance values are incorrect (by a significant amount)

High resistance cell

Problems with Cells

J1772 Troubleshooting

CANBUS Elcon Charger isn’t charging, but should be (for standard Orion BMS)

Charger turns off before battery pack reports full state of charge

Diagnosing State of Charge Calculation Jumps

Discharge or charge relay turns off too soon

Cell voltages drop after the charge completes

Problems with Charging and State of Charge

Relays don’t turn on

Problems with Relays

Orion Jr. BMS does not power up (LED stays off)

Problems with the Orion Jr. BMS

Cell voltages appear incorrect (when under load)

Diagnosing Incorrect Cell Voltage Readings

Problems with Voltages

Orion Battery Management System Troubleshooting

Using the Orion BMS With Victron Equipment

Orion BMS Tesla Module Integrations

Orion BMS With Tesla Modules

EVIC Display By Andromeda Interfaces

Andromeda Display Integration