TSB's

Fouled Ford transmission

Some 2009 F-150, E-150, Crown Victoria, Grand Marquis and 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 diagnostic trouble codes for this concern are related to transmission internal solenoids as follows: 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 the Crown Victoria, Grand Marquis or Town Car; or BJB location F79 in E 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. If the transmission build date is before 12/1/2008 and the vehicle exhibits the described symptoms, go to Step 2. If the transmission build date is on or after 12/1/2008, 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 the internal wiring harness routing. Follow the workshop manual, section 307-01 for transmission fluid pan removal and wire harness replacement.

At left is the correct harness routing. At right shows an example of the harness being pinched at the pan rail area (see arrow).
<p>At left is the correct harness routing. At right shows an example of  the harness being pinched at the pan rail area (see arrow).</p>

 

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