Help Song plus / sealion 6 / seal u
BYD Song Plus DM-i – Engine will not start, stuck in EV mode, DTC P184100 The car runs perfectly in EV mode and drives normally inside the city, but the gasoline engine never starts and I cannot switch to HEV or SAVE mode. Important details: • I did NOT buy the car from the official dealer • The car is OUT OF WARRANTY • The dealer refused to diagnose or repair it – which honestly makes no sense I went to a local workshop and they scanned the car using an OBD device. The fault code is: P184100 – Too high voltage of battery cell in collector module #8 (PACK2) The code CANNOT be cleared and comes back immediately. Battery behavior: • The HV battery charges normally with an external charger • I charged it to 100% and the charging process was completely normal • The car drove perfectly for about 20 km after full charge • Then the engine still would NOT start • Current SOC is around 40% • 12V battery tested GOOD by a technician So the strange part is: The car drives perfectly as an EV with no issues at all, but the engine start is completely blocked. My questions: 1. Can DTC P184100 prevent the engine from starting? 2. Is this definitely a BMS / battery module issue? 3. Has anyone fixed this without replacing the full battery pack? 4. What gives the permission for the engine to start in this car?
