2003 Ford ZX2 AutomaticFACTORY OEM SERVICE PROCEDURE

Digital Signal Processing Module

WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The digital signal processing module (if equipped) uses the medium speed CAN for communication with the diagnostic tool. The digital signal processing module works with the audio unit allowing the listener expanded signal manipulation and audio control.

Check the medium speed CAN circuits between the digital signal processing module C4326a and the DLC C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the medium speed CAN, damage to the DLC C251, or damage to digital signal processing module C4326a.

For additional digital signal processing module information, refer to ENTERTAINMENT SYSTEM - GENERAL INFORMATION .

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
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  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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