E300 not switching from engine to electric
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e300 hybrid estate
E300 not switching from engine to electric
E300 BlueTEC Hybrid 2015 ... Recently had an “auxiliary battery malfunction” message appear. At the same time noticed that “HOLD” did not engage anymore, and additionally the engine no longer cut out and electric take over when coasting. Replaced the auxiliary battery and the “auxiliary battery malfunction” message has gone, and “HOLD” now engages, but the engine still does not cut out when coasting (as it used to do). Nor does the eco start stop seem to be working. Is this feature associated with the auxiliary battery or is it just coincidental that the problem occurred at the same time. Either way, what are the potential causes and solutions? I should add, the electric motor battery is showing as charged and also charging when driving (on the dashboard displays). Thanks
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2019 G70 6MT & 2022 Ford Maverick XL
The "HOLD" function is definitely tied to the auxiliary battery. But have you tried replacing the regular 12v battery? Often that causes issues with stop/start not working in the non-hybrids. It's worth a shot.
Thread Starter
Newbie
Joined: Jan 2021
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e300 hybrid estate
Thank you! I have boosted the regular 12v battery with an overnight charge and all functions are back to normal. If they drop off again I will know to replace the battery. Once again, appreciate your help. Thanks
