If its an auto box fault then you probably referring to a shift solenoid fault. This is located inside the transmission pan. There are 4 solenoids (2 shift ) so use scan tool to confirm which one. To make matters worse the scan tool will say shift valve circuit open or short or performance. But in reality can be a burst valve body gasket on the solenoids hydraulic circuit. For specialist www.fedauto.co.uk
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