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Home >> Dodge and Ram >> 2013 >> Durango R/T, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 112 (Transmission Control Module (TCM) - Nag1 Automatic Transmission) >> Diagnosis And Testing >> P0731-Gear Ratio Error In 1ST >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 2012 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.
Possible Causes
PINION FACTOR IS NOT PROPERLY PROGRAMMED
LOW TRANSMISSION FLUID
OTHER TRANSMISSION DTCS PRESENT
INTERNAL TRANSMISSION FAILURE

Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to  STANDARD PROCEDURE  .