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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
P1611low severityPowertrain

MIL Request Signal Circuit Voltage Low

on 2021 Hyundai Tucson 2.5L I4 · AWD

What this code means

The PCM has detected a low voltage condition on the MIL (Malfunction Indicator Lamp) request signal circuit. The circuit that controls the Check Engine Light on the instrument cluster is not functioning at the correct voltage.

Symptoms

  • Check Engine Light may not illuminate when it should
  • Possible false MIL illumination
  • Instrument cluster communication issue

Common causes

  • Short to ground in MIL control circuit
  • Faulty instrument cluster
  • Wiring issue between PCM and instrument cluster
  • PCM MIL driver failure
  • Corroded connector

Diagnostic steps

  1. Check MIL operation with scan tool MIL command
  2. Inspect wiring between PCM and instrument cluster
  3. Test MIL circuit for shorts to ground
  4. Check instrument cluster connector
  5. Verify PCM MIL output

Repair notes

Repair the wiring in the MIL control circuit or replace the instrument cluster if it is at fault.

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