Engine-Codes - Ford - U0004 FORD

U0004 FORD - High Speed CAN Communication Bus (+) Low

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

U0004 FORD Possible Causes

  • Diagnosis of this Diagnostic Trouble Code (DTC) is accomplished via the vehicle symptom(s)
  • Check for more codes
  • Faulty Control Module
  • Control Module harness is open or shorted
  • Control Module circuit poor electrical connection

How is the U0004 FORD code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the U0004 FORD code

Labor: 1.0

The cost to diagnose the U0004 FORD code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

U0004 FORD Meaning

Multiplexing is a method of sending 2 or more signals simultaneously over a single circuit. Multiplexing allows 2 or more electronic modules (nodes) to communicate over a twisted wire pair [data (+) and data (-)] network. The information or messages that can be communicated on these wires consists of commands, status or data. Multiplexing reduces the weight of the vehicle by reducing the number of redundant components and electrical wiring. The vehicle has 4 module communication networks connected to the DLC, located under the instrument panel. The communication networks are: HEV High Speed Controller Area Network (HS-CAN), High Speed Controller Area Network (HS-CAN), Medium Speed Controller Area Network (MS-CAN) and Infotainment Controller Area Network (I-CAN). The Diagnostic Trouble Code (DTC) U0004 sets when a High Speed Controller Area Network (HS-CAN) fault was present at a point in time. The fault is not currently present since the module is communicating with the scan tool.

More Information

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