MajorCommonElectrical

Mazda CX-60: G25E-C PHEV High-Voltage Battery Management Software Mismatch

G25E-C PHEV High-Voltage Battery Management Software Mismatch is a common electrical fault on the Mazda CX-60 on the 2022–2023 cars, and we rate it major. Putting it right costs $0 to $600 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 11 documented faults on the Mazda CX-60.

Vehicle: Mazda CX-60
Only on: plug-in
Years: 2022–2023
Fuel: hybrid
Gearbox: auto
System: Electrical

This page covers the Mazda CX-60 as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Mazda CX-60 faults11 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph for this fault yet. We would rather show none than show a picture of something else.

What goes wrong

The CX-60 PHEV uses a 17.8 kWh lithium-ion traction battery managed by a Mazda-proprietary BMS. Early production vehicles (2022-early 2023) had a software mismatch between the BMS calibration and the inverter control module, causing the displayed state-of-charge to diverge from the actual cell capacity over charge-discharge cycles. Affected vehicles showed the EV range indicator reading 5-12 km higher than achievable range, and in some cases the BMS triggered a protective capacity limit reducing usable battery to approximately 60% of rated capacity. Mazda issued TSB PHEV-BMS-2023-01 covering a BMS and inverter co-update, which is applied free of charge at any Mazda dealer.

What you would notice

Displayed EV range is consistently 8-15 km higher than actual driving range in real conditions
High-voltage battery warning light illuminates during or after fast charging
Vehicle unexpectedly switches from EV mode to engine-only mode before the state-of-charge reaches zero
Maximum usable EV range has decreased noticeably since delivery without high-mileage explanation

How to check it

Where to look. High-voltage battery pack under rear floor, power electronics module in engine bay

Charge the vehicle to 100% at a Type 2 AC charger and note the displayed EV range.
Drive in EV-only mode and compare actual consumption to displayed estimate.
Request a dealer health check that reads individual cell voltages and confirms BMS firmware version matches the TSB-specified calibration.
Check for any stored BMS or inverter fault codes.

What it costs to put right

$0 to $600 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“Has the PHEV battery management system software been updated to the Mazda TSB-specified firmware version, and can you show the dealer record confirming both BMS and inverter were updated together?”
“Has the displayed EV range ever been significantly higher than the actual achievable range, or has a high-voltage battery warning appeared?”

Now check the Mazda CX-60 you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.

Mazda CX-60 buyer questions

Is g25e-c phev high-voltage battery management software mismatch serious on a Mazda CX-60?

We rate it major and common on the Mazda CX-60. The CX-60 PHEV uses a 17.8 kWh lithium-ion traction battery managed by a Mazda-proprietary BMS. Early production vehicles (2022-early 2023) had a software mismatch between the BMS calibration and the inverter control module, causing the displayed state-of-charge to diverge from the actual cell capacity over charge-discharge cycles. Affected vehicles showed the EV range indicator reading 5-12 km higher than achievable range, and in some cases the BMS triggered a protective capacity limit reducing usable battery to approximately 60% of rated capacity. Mazda issued TSB PHEV-BMS-2023-01 covering a BMS and inverter co-update, which is applied free of charge at any Mazda dealer.

How much does it cost to fix on a Mazda CX-60?

$0 to $600 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Mazda CX-60 years are affected?

Our research records this fault on the 2022–2023 Mazda CX-60. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

Charge the vehicle to 100% at a Type 2 AC charger and note the displayed EV range. Drive in EV-only mode and compare actual consumption to displayed estimate. Request a dealer health check that reads individual cell voltages and confirms BMS firmware version matches the TSB-specified calibration. Check for any stored BMS or inverter fault codes. Look here: High-voltage battery pack under rear floor, power electronics module in engine bay