Diagnostic trouble code
P1575 — Motor Power Inverter Module Voltage Problem (Honda IMA)
What it means in plain English
The inverter side of your Honda's hybrid system is reporting a voltage problem, not the pack.
P1575 is a Honda-specific code covering the Motor Power Inverter Module — the electronics that convert the pack's DC into the AC the motor uses. It is set when the module reports a voltage it does not expect. This matters commercially: it is not a battery code, and a car carrying P1575 alone does not need a pack. It often appears alongside genuine battery codes on an old car, which is exactly when it gets mistaken for one.
Which Toyota and Lexus models this applies to
Honda Integrated Motor Assist hybrids — Insight, Civic Hybrid, Accord Hybrid and CR-Z.
Possible causes
Plural on purpose. Any of these can produce this result — which is exactly why a code is not a diagnosis.
- A fault inside the motor power inverter module itself.
- High-voltage cable or connector resistance between the pack and the inverter.
- A failing motor control module or its supply.
- Low or unstable pack voltage presenting to the inverter as a voltage fault.
- 12V supply problems affecting the control electronics.
- Corrosion at a high-voltage connector, common on cars that have been through water.
What a professional diagnostic process should check
- 1Separate the inverter fault from any battery fault stored with it — establish which came first.
- 2Measure pack voltage under load at the inverter's input, not just at the pack.
- 3Inspect high-voltage cables and connectors for resistance, corrosion and heat marking.
- 4Check the 12V supply and grounds feeding the control modules.
- 5Confirm the inverter's own cooling is working.
- 6Check for Honda service bulletins covering the inverter on the model year.
What you can safely do now
- Ask specifically whether this code is being used to justify a battery quote. It shouldn't be on its own.
- Get the full list of stored codes, not just the one you were told about.
- Note whether the fault appears when the car is hot, cold, or both.
What not to do
- Don't buy a pack on the strength of P1575 alone.
- Don't clear it before the whole code set has been recorded.
- Don't ignore it — inverter faults can escalate, and on these cars the inverter costs more than the battery.
When towing or urgent service is appropriate
Tow it if the car loses power, refuses to start, or warns about the hybrid system while driving. Inverter faults are less predictable than battery wear and less safe to ride out.
Not sure which category you're in? Call 623-323-0737 and describe what the car is doing. That call is free and it might save you a tow — or a much bigger repair.
Do not replace parts based on a code alone
Do not replace parts based on a code alone. A diagnostic trouble code tells you which circuit or system reported a problem — it does not identify which component failed. The same code can be set by several different faults, and clearing it without a diagnosis just hides the evidence. This page is educational; your vehicle needs its own inspection before any repair decision.
P1575 — common questions
Is P1575 a battery code?
Why did I get P1575 together with battery codes?
Get P1575 diagnosed properly
Tell us the code, the year and model, and what the car is doing. We'll tell you what we'd check — and we won't quote a repair from a code.
Not sure what your hybrid needs? We'll work it out with you.
We come to you, test the pack, the 12V and the cooling, and you get a written quote before anything is decided. No obligation.