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Home >> Subaru >> 2017 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle (Diagnostics) >> Automatic transmission system >> DTC P0601: Internal Control Module Memory Check Sum Error
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DTC P0601: Internal Control Module Memory Check Sum Error

Circuit description

The value calculated by the transmission control computer is compared with the data stored in the transmission control computer ASSY when IG is ON, and when they do not match 2 times consecutively, DTC is detected and the learning is prohibited. If the problem persists, cut continuity to all the solenoid (lock at 4th gear).

DTC No. SAE/TCCS DTC detecting condition
  1. Diagnosis condition
  2. Abnormal condition
  3. Abnormal period
  4. Other
Inspection parts
P0601
  1. IG ON When DTC clear required
  2. Transmission control computer ASSY, internal error
  3. -
  4. trips
  • Transmission control computer ASSY

Monitor description

TCM observes inner operation. If a defect is found in inner operation, TCM turns on MIL and records diagnostic codes.

MONITOR STRATEGY DESCRIPTION

Applicable diagnostic codes P0601: Internal Control Module Memory Check Sum Error
Required sensor/component TCM
Operation frequency Once per driving cycle
Period 2 times
MIL operation Immediate
Operation order None

TYPICAL ENABLING CONDITIONS

Either of the following conditions must be satisfied: condition (A) or (B)

ENABLING CONDITIONS DESCRIPTION

If the following diagnostic code is not present, the monitor operates. None
IG SW is turned from OFF to ON. Yes
ENABLING CONDITIONS DESCRIPTION

If the following diagnostic code is not present, the monitor operates. None
A request to clear the diagnostic code from the diagnosis tool is received. Yes
TYPICAL MALFUNCTION THRESHOLDS DESCRIPTION

Total data calculated by flash ROM None (flash ROM checksum data)

Inspection steps

NOTE: Read the freeze frame data using the SSM4. A part of the engine running conditions under which the engine trouble occurred is recorded in the freeze frame data, which is useful for troubleshooting.
  1. Replacement of transmission control computer ASSY
    1. Replace the transmission control computer ASSY. (Refer to Transmission control computer ASSY )

    Next: AT unit correction (refer to Inspection for problems that do not normally occur )