Volvo V60 permanent thermostat code issue after ECM update with no warranty coverage on Volvo V60

Some Volvo V60 owners report experiencing a permanent thermostat code issue, such as ECM-P059700, particularly after an ECM update, which may indicate a fault in the thermostat heater control circuit. These owners note that if the thermostat fault persists post-update, it could signal deeper problems that might lead to additional malfunctions, including a no-start condition or a dead battery. In situations where warranty coverage is unavailable, some owners find it necessary to weigh the costs of further diagnostics and repairs. Additionally, those facing ongoing thermostat faults are advised to consult with a qualified mechanic or Volvo specialist for accurate diagnosis and potential solutions, which may involve replacing the thermostat housing or, in severe cases, the ECM itself. For DIY enthusiasts, understanding the causes of the OBD code P0597, such as an open or short circuit in the thermostat heater control, is essential for troubleshooting, though professional guidance is recommended to avoid complications.