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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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Repairs0Labor1040Torque1598Fluid17DTC3336Battery2Maintenance0Recalls5
P0864moderate severityPowertrain

TCM Communication Circuit Range/Performance

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The signal on the transmission control module communication circuit is outside the expected range or performing erratically. This indicates a data quality problem rather than a total loss of communication.

Symptoms

  • Intermittent shift problems
  • Transmission warning light
  • Delayed gear engagement

Common causes

  • Intermittent wiring fault
  • Corroded connector pins
  • Faulty TCM
  • Signal interference on data bus

Diagnostic steps

  1. Retrieve all stored codes
  2. Inspect connectors for corrosion
  3. Wiggle-test harness while monitoring data
  4. Compare TCM signal to specification
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Other Powertrain codes on this vehicle

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