The complaint
During the overhaul process of a Ford 4R70W transmission, it was necessary to replace the hard wire frame and case connector. After repairs were completed and the technician prepared to take the vehicle for a road test, the transmission took off in a higher gear and the MIL illuminated. The PCM was scanned and various solenoid codes were set which were not present originally.
The cause
An aftermarket sub-standard case connector was installed which had two terminals pushed into the connector which prevented contact with the hard wire frame (see the image above). One of these terminals was the 12-volt solenoid supply circuit, which caused the high gear start.
The correction
When the hard wire frame and case connector were replaced with Ford original equipment parts, the codes were cleared and did not return.
Service information
Hard Wire Frame: F8AZ-7G276-BA
Hard Wire Frame Connector: F8AZ-7G276-A
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