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1998 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1042Torque1610Fluid17DTC3334Battery2Maintenance0Recalls5
P0898moderate severityPowertrain

Transmission Control System MIL Request Circuit Low

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The transmission control module is commanding the malfunction indicator lamp but the request circuit reads low voltage. This indicates a wiring or module communication fault.

Symptoms

  • Check engine light behavior abnormal
  • Transmission warning present
  • Possible limp mode

Common causes

  • Short to ground in MIL request circuit
  • Faulty transmission control module
  • Damaged wiring or connectors
  • PCM/TCM communication fault

Diagnostic steps

  1. Check MIL request circuit for shorts to ground
  2. Inspect wiring and connectors at TCM
  3. Verify PCM and TCM communication
  4. Test module voltages and grounds
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