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Home / DTC / U0493 — Invalid Data Received From Personal Computer

U0493 — Invalid Data Received From Personal Computer

Detailed page for trouble code U0493.

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Code

U0493

Generic U — Network/User

Invalid Data Received From Personal Computer

Brand: Generic
Type: U — Network/User
Views: UK: 16 EN: 27 RU: 18
AI status
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Page language: EN

Causes

  • Faulty or misbehaving Personal Computer (PC) module (software or hardware fault)
  • Corroded, loose or damaged wiring or connectors between modules
  • CAN/LIN/FlexRay bus faults (open, short to voltage/ground, missing termination)
  • Intermittent power, ground, or battery voltage issues causing message corruption
  • Software version mismatch or corrupted module calibration/programming
  • Electromagnetic interference (EMI) or noise on the vehicle data bus

Symptoms

  • Malfunction Indicator Lamp (MIL) or communication warning lamp illuminated
  • Loss or intermittent operation of features controlled by the PC module (infotainment, vehicle personalization, user inputs)
  • Error messages on dash or infotainment display
  • Unresponsive or frozen user interface, erratic behavior
  • Other U-codes present (bus-related communication codes)

What to check

  • Read all stored and pending DTCs and freeze frame data from all modules using a capable scan tool
  • Check battery voltage and charging system for stability during the fault occurrence
  • Visually inspect wiring harnesses and connectors for damage, corrosion, or loose pins at the PC module and related modules
  • Inspect CAN/LIN bus termination resistors and measure bus voltages with key ON and engine running
  • Check for multiple modules reporting communication faults or similar U-codes
  • Verify current software/flash levels for involved modules and consult technical service bulletins

Signal parameters

  • Message ID / PGN (identifier) of PC-originated frames
  • Source module address and expected source address
  • Data length (bytes) and expected byte layout for PC messages
  • Message frequency / expected transmission interval (Hz or ms)
  • Sequence counter, CRC or checksum fields if used by protocol
  • Timestamp of received frames and time delta between repeats

Diagnostic algorithm

  1. Use a scan tool to record U0493 and any related U-codes; note freeze frame and time of occurrence.
  2. Identify which module logged the U0493 and confirm which module is identified as the PC in wiring/service documentation.
  3. Inspect connectors and wiring at the PC module and at the receiving module(s) for corrosion, bent pins, water intrusion, and secure mating; repair as needed.
  4. Verify battery voltage and grounds; check for intermittent supply drops during operation that could corrupt messages.
  5. With a CAN/LIN sniffer or scope, capture bus traffic while recreating the fault; look for malformed frames, repeated error frames, missing acknowledgements, or address conflicts.
  6. Check bus termination resistors and measure idle bus voltages (CAN ~2.5V differential idle). Repair wiring or termination faults.
  7. If bus traffic shows malformed messages originating from the PC module, consider reflash/update of PC software per manufacturer procedures or replace the PC module if available and confirmed defective.
  8. After repairs, clear codes, perform a functional test/road test, and monitor for reoccurrence. If intermittent and not reproduced, continue monitoring and check for installation or environmental causes (moisture, chafing).
  9. Consult manufacturer service information, wiring diagrams, and TSBs before module replacement; follow any required programming/relearn procedures after module replacement.

Likely causes

  • Loose/corroded connector or damaged harness to the PC module or receiving module
  • Faulty PC module software or firmware causing malformed messages
  • Bus wiring fault or missing/failed termination resistor
  • Low battery or unstable supply voltage during communication
  • Receiving module interpreting data with wrong message format (software mismatch)

Fault status

⚠️ Status
Invalid or corrupted data received from the Personal Computer module on the vehicle communications bus; message could not be validated or parsed by the receiving module.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0073 U0401 U0415 U0416 U0452
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