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Home / DTC / U0554 — Invalid Data Received From Accessory Protocol Interface Module

U0554 — Invalid Data Received From Accessory Protocol Interface Module

Detailed page for trouble code U0554.

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Code

U0554

Generic U — Network/User

Invalid Data Received From Accessory Protocol Interface Module

Brand: Generic
Type: U — Network/User
Views: UK: 21 EN: 20 RU: 24
AI status
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Page language: EN

Causes

  • Faulty APIM (internal failure or corrupted software)
  • Intermittent or damaged wiring/connectors to the APIM
  • Poor or missing module power or ground
  • CAN/LIN bus faults (shorts, opens, high resistance, missing termination)
  • Incompatible or incorrectly programmed replacement module
  • Aftermarket accessory or retrofit interfering with communications

Symptoms

  • DTC U0554 stored; may be accompanied by other U-series communication codes
  • Loss or intermittent operation of accessory functions (infotainment, phone, USB, steering wheel controls)
  • Unresponsive touchscreen or media features
  • Random resets or reboots of accessory systems
  • Multiple modules reporting communication errors

What to check

  • Connect a professional scan tool and confirm U0554; read freeze frame and related U-codes
  • Check for additional network communication codes (U0xxx) recorded by other modules
  • Visually inspect APIM connector and wiring for corrosion, bent pins, water ingress, or damage
  • Verify battery voltage at the APIM power terminal with ignition on and engine off
  • Verify good chassis and module ground(s) at the APIM
  • Backprobe or use breakout box to monitor CAN/LIN signals while operating affected functions

Signal parameters

  • Supply voltage at APIM: battery nominal ~12 V (check for >11 V during tests)
  • Ground: near 0 V reference at module ground pin
  • CAN bus idle voltages (typical): CANH ≈ 2.5–3.5 V, CANL ≈ 1.5–2.5 V; dominant state CANH ≈ 3.5 V, CANL ≈ 1.5 V
  • Expected CAN differential idle ≈ 0 V when measured DC, or nominal differential ~0 V with proper recessive state; differential pulses when active — verify with oscilloscope
  • LIN bus (if present) recessive ~ battery voltage via pull-up; dominant low to ground

Diagnostic algorithm

  1. With a capable scan tool, retrieve U0554 and any related codes; record freeze frame data
  2. Attempt to clear the code and reproduce; note if code returns and under what conditions
  3. Inspect APIM connector, look for corrosion, pushed-out pins, moisture, or bent terminals; repair as needed
  4. Verify battery voltage and engine off/on conditions; charge battery or perform voltage checks if low
  5. Verify module ground(s) resistance to chassis (
  6. Check CAN/LIN wiring continuity and for shorts to battery or ground; isolate segments if needed
  7. Measure CANH/CANL voltages at the APIM with ignition on; compare to expected ranges and probe with oscilloscope to look for noise, missing frames or corrupted signals
  8. Check for proper termination (two 120 ohm resistors in parallel ≈60 ohms) across CANH and CANL at the network ends
  9. Disconnect suspected aftermarket accessories or recently installed modules and re-test
  10. If wiring and power/ground are good, confirm APIM software calibration and flash level; reflash or update per manufacturer service information
  11. If directed by manufacturer diagnostics and fault persists, replace APIM and program/configure replacement module, then recheck network operation

Likely causes

  • Corroded or loose APIM connector pins
  • Open or shorted CAN high/low or LIN communication wires
  • Missing ground or low battery voltage to the APIM
  • Module software mismatch or failed reflash
  • Other modules on the bus sending corrupted frames

Fault status

⚠️ Status
Invalid or corrupted data received from the Accessory Protocol Interface Module. Communication fault detected on vehicle network; related accessory functions may be affected.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0073 U0115 U0121 U0131 U0140
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