Peugeot 508 Hybrid 225 Mk2

The 508 Hybrid's 11.8 kWh lithium-ion traction battery has been subject to at least three separate EU recalls: a cell voltage mismatch issue (2019 production), faulty battery monitoring software allowing undetected overheating (2019-2022), and water penetration causing corrosion of the battery box (2019-2023). Combined, these recalls affect over 100,000 vehicles across the 508 and 3008 platforms. While the underlying problems have been addressed via software updates and hardware checks at Peugeot dealers free of charge, a used buyer must verify with the VIN that all recalls have been completed. If the traction battery itself needs replacement outside warranty, expect €3,000-5,000 for a refurbished unit or €6,000-8,000 for a new OEM pack including labor.

The onboard charger module is integrated near the battery pack and requires significant disassembly to access. Owners have reported the car indicating 'charging complete' when the battery is actually empty, or refusing to accept charge from a wall box or public charger. The 7.4 kW optional charger appears slightly more prone to failure than the standard 3.7 kW unit. Peugeot has acknowledged faults with certain charger batches. Replacement involves removing rear seat components and partial chassis disassembly, resulting in high labor costs. A separate recall in 2023 addressed charging cable safety function failures on some models.

The hybrid control unit relies on multiple software modules for battery management, energy distribution, and charge scheduling. Owners widely report the car refusing to enter electric mode, the petrol engine running continuously despite a charged battery, or the traction battery showing incorrect state of charge. A TSB from April 2023 notes that the engine may be forced to run for humidity protection if the car has not been driven for an extended period, requiring approximately 100 km of steady driving to unlock EV mode again. Many cases are resolved by software updates at the dealer (typically 1-2 hours of labor at €100-150/hour), though persistent cases have required replacement of battery sensors or the hybrid control module (€500-800 including labor). Some owners report up to 12 software updates being applied in a single visit.

The EP6FADTX 1.6 turbo engine is the latest evolution of the PSA/BMW Prince family. While improved over earlier EP6DT variants, the turbocharger remains a known wear item. Approximately 15% of owners report turbo-related issues after 100,000 km, particularly wastegate rattle or boost control failures. Short trip driving accelerates carbon buildup on intake valves and can cause the turbo actuator to stick from soot deposits. A replacement turbocharger with labor runs €1,500-2,500 at a specialist, or up to €3,000 at a Peugeot dealer. Preventive measures include using premium fuel, allowing proper warm-up, and periodic spirited driving to clear deposits.

The Aisin EAT8 (TG-81SC) is generally robust, but the hybrid variant adds complexity with the integrated electric motor and clutch arrangement. Owners report a mild judder or shudder at low speeds, particularly during gentle acceleration from a stop. This is often caused by torque converter fluid degradation or valve body deposit buildup. Peugeot calls the transmission fluid 'lifetime fill,' but specialist consensus is that a fluid change every 60,000-80,000 km (approximately €300-400 at an independent, €500-600 at a dealer) significantly reduces these symptoms. If left unaddressed, valve body or torque converter damage can escalate repair costs to €1,500-2,500.

The 508 Hybrid does not use a traditional alternator. Instead, a DC-DC converter draws power from the high-voltage battery to charge the 12V system. When driving exclusively in electric mode for extended periods, the 12V battery may not charge adequately, particularly on short journeys where the DC-DC converter has insufficient runtime. Symptoms include the car refusing to start, dashboard warning lights, or system reboots. A replacement AGM 12V battery costs €150-250. Software updates have improved the charging algorithm, but keeping the 12V battery in good condition and occasionally running in hybrid mode helps prevent recurring issues.

The i-Cockpit infotainment system can freeze or go black during use. The workaround is holding the phone button for 10 seconds or disconnecting the 12V battery briefly. Peugeot has issued several software updates to address stability, but the issue persists for some owners even after updates. While largely an annoyance rather than a safety issue, it can temporarily disable climate controls, navigation, and the reversing camera. Replacement of the head unit (if needed beyond software) costs approximately €400-500 plus labor.