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P1DF3 · Manufacturer communications

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

P1DF3 ← What does this code mean?

9 Results

08-226-26 REV. A ↗

RAM · 2026-06-16

Flash: Electronic Shift Module (ESM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0607-00 - ECU Internal Performance. NOTE: DTC P0607-00 will be stored in the Automatic Gearbox Shifter Module (AGSM)/Electronic Shift Module (ESM). ● P1DF3-00 - ECU Not Initialized. NOTE: DTC P1DF3-00 will be stored in the Transmission Control Module (TCM). Customers may also comment on one or more of the following: ● Shifter not able to move out of Park with "Service Shifter" message showing on Instrument Panel Cluster (IPC). ● PRNDL lights flashing. **This bulletin involves inspecting and possibly reprogramming the ESM with the latest software.**

21-011-25 REV. B ↗

RAM · 2025-12-20

Flash: Transmission Control Module (TCM) Updates *Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P1B14-00 - Park By Wire Unintended Park Position. ● P1DF3-00 - ECU Not Initialized.** The customer may describe one or more of the following: ● **Secure idle feature not working with Powerpanel On. ● When shifting from Drive to Reverse and vice versa, the transmission detects a mismatch in Neutral as the gear shifter goes from Drive to Reverse through Neutral (D-N-R or R-N-D) and flashes the Neutral indication blinking on the shifter. ● The gear shifter takes too long to get ready when the driver starts the car, and the transmission system couldn't recognize which gear…

21-015-25 REV.A ↗

RAM · 2025-07-19

Flash: Transmission Control Module (TCM) Updates **Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P1B14 - Park By Wire Unintended Park Position. ● P1DF3 - ECU Not Initialized.** The customer must describe one or more of the following: ● **Secure Idle feature not working with Powerpanel on. ● When the driver tries to shift from Drive to Reverse and vice versa, transmission detects a mismatch in Neutral as the gear shifter goes from Drive to Reverse through Neutral (D-N-R or R-N-D) and flashes the Neutral indication blinking on the shifter. ● The transmission continues to stay in Park sometimes when the driver shifts to Drive or Reverse via gear shifter. Warning…

S2521000002 ↗

RAM · 2025-06-09

Malfunction Indicator Lamp (MIL) Illuminated. Diagnostic Trouble Code (DTC) P1DF3 – ECU Not Initialized, Set.

2100921 ↗

RAM · 2021-02-27

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set:P1DDE-00 - Ignition Run-Start Input 1-2 Correlation. P1DF3-00 - ECU Not Initialized. P07E4-00 - Unable To Engage Park. P0735-00 - Gear 5 Shift Incorrect Ratio. The customer may also notice the following condition: Drivetrain "clunks" or harsh/rough upshifts, specifically going into 2nd, 3rd or 4th gears. The following enhancements are also included in this software update:Improvement to the 5-3-2 downshift to preventDTC P0735-00. Shifter auto-position correction…

21-009-21 ↗

RAM · 2021-02-27

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set:P1DDE-00 - Ignition Run-Start Input 1-2 Correlation. P1DF3-00 - ECU Not Initialized. P07E4-00 - Unable To Engage Park. P0735-00 - Gear 5 Shift Incorrect Ratio. The customer may also notice the following condition: Drivetrain "clunks" or harsh/rough upshifts, specifically going into 2nd, 3rd or 4th gears. The following enhancements are also included in this software update:Improvement to the 5-3-2 downshift to preventDTC P0735-00. Shifter auto-position correction…

21-033-20 ↗

RAM · 2020-04-25

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following DTCs have been set:P1DDE-00 - Ignition Run-Start Input 1-2 Correlation. P1DF3-00 - ECU Not Initialized. P07E4-00 - Unable To Engage Park. P0735-00 - Gear 5 Shift Incorrect Ratio. The following enhancement is included in this software update:Improvement to the 5-3-2 downshift to prevent DTC P0735-00. Shifter auto-position correction with ignition in RUN/ACC positions during an AutoPark event.

21-011-20 ↗

RAM · 2020-02-15

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following DTCs have been set:P1DDE-00 - Ignition Run-Start Input 1-2 Correlation(Sales Code DFR Only). P1DF3-00 - ECU Not Initialized(Sales Code DFR Only). P0456 - EVAP System Small Leak. P0733-00 - Gear 3 Shift Incorrect Ratio (while operating in 4-Lo range). P0716-00 - Input Shaft Speed Sensor 1 Performance. P0721-00 - Output Shaft Speed Sensor Circuit Performance. P1DB6-00 - Vehicle Speed Signal Performance. P1DAB-00 - Vehicle Speed Undetermined. P215C-00 - Output Shaft Speed Wheel Speed Correlation. P0607-00 - ECU…

21-009-20 ↗

RAM · 2020-02-11

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Some customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following DTCs: P1DDE-00 - Ignition Run-Start Input 1-2 Correlation(Sales Code DFR Only). P1DF3-00 - ECU Not Initialized(Sales Code DFR Only). P0733-00 - Gear 3 Shift Incorrect Ratio (while operating in 4-Lo range). P0716-00 - Input Shaft Speed Sensor 1 Performance. P0721-00 - Output Shaft Speed Sensor Circuit Performance. P1DB6-00 - Vehicle Speed Signal Performance. P1DAB-00 - Vehicle Speed Undetermined. P215C-00 - Output Shaft Speed Wheel Speed Correlation. P0607-00 - ECU Internal Performance. P1DAC-00-Engine…