TSB 07-9-10 6.4L - PTO/BCP - DISENGAGES WITH VEHICLE BODY MOVEMENT - Diesel Forum

Diesel Jay · 05-03-2007, 12:09 PM

FORD: 2008 F-450, F-550

ISSUE:
Some 2008 F450/550 Super Duty vehicles equipped with 6.4L diesel engine may lose power take-off (PTO) or battery charge protection (BCP) function with any small body movement. This includes movement as light as opening a door, or stepping on the bumper. This concern is only on vehicles using the Ford stationary elevated idle control (SEIC) to provide the required engine speed increase and its circuit links to PTO engagement and battery state. When this occurs the engine speed returns to base idle of 650 RPM, and any PTO and BCP circuit links are disconnected. In normal diesel engine operation SEIC automatically reactivates after 3 seconds if no disabling condition remains present, returning to its preset target speed, and re-enabling the PTO or BCP function.

ACTION:
Reprogram the powertrain control module (PCM) to the latest calibration using IDS release 48.12 and higher or 49.2 and higher. This new calibration is not included in the VCM 2007.5 DVD.This calibration filters out small vehicle speed signals shutting down SEIC. Calibration files may also be obtained at www.motorcraft.com. Vehicle road speed signal is an SEIC disabler, and this calibration makes that signal less sensitive.

WARRANTY STATUS:
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage

frobozz · 05-03-2007, 12:17 PM

As someone who's done embedded programming in the past, I find bugs like this fascinating. Someone said "if the vehicle starts to move, we need to shut down the PTO" and whoever programmed it said "If I see any signal from the VSS, the vehicle is moving" when in fact, as they point out, that's not necessarily the case.

If silly stuff like that is what 6.4L TSBs are going to consist of, I have much higher hopes for this engine!

Duncan