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2021 HYUNDAI TUCSON
2.5L I4•AWD•AUTOMATIC•gas
1 active safety recall on this vehicle — view recalls
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Repairs425Labor501Torque3434Fluid9DTC1092Battery1Maintenance0Recalls1
P1586moderate severityPowertrain

AT/MT Codification Signal Not Plausible

on 2021 Hyundai Tucson 2.5L I4 · AWD

What this code means

The PCM has received a transmission codification signal that does not match the expected transmission type. The signal indicating whether an automatic or manual transmission is installed is incorrect or missing.

Symptoms

  • Check Engine Light
  • Transmission may enter limp mode
  • Incorrect shift patterns
  • Engine performance may be limited

Common causes

  • Incorrect PCM software for transmission type
  • Wiring issue in transmission codification circuit
  • Aftermarket transmission swap without PCM recoding
  • PCM connector issue
  • TCM programming mismatch

Diagnostic steps

  1. Verify PCM software matches installed transmission type
  2. Check transmission codification wiring
  3. Inspect PCM and TCM connectors
  4. Verify correct PCM part number for vehicle configuration
  5. Reprogram PCM if needed

Repair notes

Reprogram the PCM with the correct transmission configuration software.

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