when starting from cold fisrt time of the day,driving along with the temp gauge approx halfway to normal operating level the auto drops to a low drive and the transmission light comes on,stop vehicle,switch off,restart,ok for the rest of the day
The light coming on indicates a fault(s) This will put you into third gear losing pressure reduction hence thump.The codes need reading to be certain of fault. Also look at live data. Commonest fault is pressure regulation due to solenoids out of spec. In nomal use the seat is hammered and no longer controls pressure correctly. The difference with actual to commanded pressure above a limit will bring light on. For specialist www.fedauto.co.uk
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