TSB's

Confused Ford transmission

Some 2009 Ford  F-150, E-150, Crown Victoria, Grand Marquis and Lincoln Town car vehicles equipped with the 4R75E transmission and a transmission build date before 12-1-2008 may exhibit improper gear selection, converter clutch operation or improper shift feel.

The cause may be an intermittent electrical open or short circuit and/or a fuse blown in the battery junction box (BJB). The most likely DTCs for this concern are related to transmission internal solenoids (P0750, P0753, P0755, P0758, P0740, P0743, P0748, P0962, P0963 and/or P0712).

Depending on shorted circuits, an open fuse might be present at BJB location F21 in Crown Vic, Grand Marquis or Town Car; or BJB location F79 in E-Series and F-Series.

The most likely cause is a mis-routed internal wiring harness being pinched between the transmission fluid pan and the main control.

1.  Check the transmission build date on the transmission tag.

a. If the transmission build date is before 12-1-2008 and the vehicle exhibits the symptoms described earlier, go to Step 2

b. If the transmission build date is on 12-1-2008 or after, this procedure does not apply. Follow normal diagnostics in the workshop manual, Section 307-01.

2. Remove the transmission fluid pan and perform a visual inspection of internal wiring harness routing.

Inspect for a pinched wiring harness between the pan and the main control. The illustration at the left shows the correct routing. At right is an example of a pinched harness.
<p>Inspect for a pinched wiring harness between the pan and the main control. The illustration at the left shows the correct routing. At right is an example of a pinched harness.</p>

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