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2009
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Liberty Limited, RWD
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Automatic Trans
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Powertrain Control Module (Pcm) - Electrical Diagnostics - 42RLE Automatic Transmission
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DTC Troubleshooting
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U0121-Lost Communication With Anti-Lock Brake Module
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Set Conditions
Set Conditions
Set Condition:
If the PCM fails to receive bus messages from the ABS M for approximately 500 ms.