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2017 CHEVROLET IMPALA

2.5L I4 EcotecAWDAUTOMATICgas
Repairs0Labor990Torque7715Fluid15DTC1938Battery2Maintenance0Recalls0
P1812critical severityPowertrain

Transmission Over Temperature Condition

on 2017 Chevrolet Impala 2.5L I4 Ecotec · AWD

What this code means

The TCM detected that the transmission fluid temperature has exceeded the maximum safe operating temperature. Excessive heat is the primary killer of automatic transmissions.

Symptoms

  • Check Engine Light
  • Transmission may enter limp mode
  • Harsh or delayed shifts
  • Hot transmission fluid smell
  • Possible loss of forward gears

Common causes

  • Low transmission fluid level
  • Clogged transmission cooler
  • Failed transmission cooler lines
  • Towing beyond capacity
  • Worn torque converter clutch causing excess heat
  • Transmission slipping internally

Diagnostic steps

  1. Check transmission fluid level and color
  2. Inspect transmission cooler and lines for restriction
  3. Test transmission temperature with scan tool
  4. Check for transmission slipping
  5. Inspect torque converter clutch operation

Repair notes

Check fluid level immediately. Inspect cooler and lines. Do not drive with overheated transmission. If fluid is burnt (dark brown/black with burnt smell), internal damage likely.

Other Powertrain codes on this vehicle

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