How to Read a Hybrid Fault Code
Hybrid vehicles store fault codes (also called DTCs — Diagnostic Trouble Codes) in their onboard computers whenever a sensor reading falls outside its expected range. A standard OBD-II reader plugs into the port under your dashboard (usually on the driver's side) and reads these codes.
For Toyota and Lexus hybrids, many battery-specific codes (especially P3000 sub-codes) require a Toyota-specific scan tool like Techstream — a standard $25 reader from an auto parts store won't show the full picture.
The code structure tells you something about the fault: P means powertrain, 0 means SAE standard, A means hybrid/EV system. Codes starting with P0A are specifically hybrid propulsion system codes. Codes starting with P3 are manufacturer-specific.
What do the warning lights mean?
Red triangle + hybrid warning
Hybrid system fault requiring immediate attention. Most Toyota/Lexus battery codes trigger this combination.
Orange IMA light (Honda)
Honda-specific IMA system warning. Almost always indicates P1449 or P1562 battery fault codes.
Check engine light only
May accompany battery codes or indicate a separate issue. Needs a scan tool to identify.
Toyota & Lexus Hybrid Battery Codes
Replace Hybrid Battery Pack
P0A80 is stored by Toyota's Hybrid Vehicle ECU (HV ECU) when the high-voltage battery pack's state of health (SOH) falls below a calibrated …
Hybrid Battery Pack Deterioration
P0A7F is Toyota's early-warning hybrid battery deterioration code — it is stored at a less severe SOH threshold than P0A80 ('Replace Battery…
Hybrid Battery System Voltage Low
P0AFA is stored when the high-voltage battery pack's total voltage drops below the minimum threshold required for safe hybrid system operati…
HV Battery Fault
P3000 is Toyota's umbrella high-voltage battery fault code. Unlike P0A80 — which specifically identifies state-of-health decline — P3000 is …
HV Battery Module Voltage Unbalance
P3006 is a more specific HV battery code than P0A80 — it indicates that the Toyota BMS has detected an unacceptable voltage difference betwe…
Hybrid Battery Voltage System Isolation Fault
P0AA6 is the only hybrid battery code that carries a genuine safety risk. Unlike P0A80 and P0A7F — which are battery capacity issues — P0AA6…
Inverter Cooling System Performance
P0A93 is an inverter cooling system fault — not a direct battery capacity code, but one that often appears in combination with battery fault…
Honda IMA Fault Codes
Battery Module Deterioration (Honda IMA)
P1449 is Honda's primary IMA (Integrated Motor Assist) battery deterioration code and the most common fault code on Honda hybrid vehicles of…
IMA Battery Pack Module Voltage (Honda)
P1562 is a Honda IMA battery sub-code that specifically indicates the IMA battery pack's overall voltage or an individual module voltage has…
Got a Code? Get a Free Diagnosis.
Don't guess at a repair when a proper diagnostic tells you exactly which modules are failing. We use Toyota Techstream and Honda-specific tools to read sub-codes that standard readers miss. Free over the phone — call or text and tell us what codes you have.