BMW DTC P1794 – Internal Transmission Control Module Memory Check Sum Error
DTC P1794 meaning on BMW
The Diagnostic Trouble Code (DTC) P1794 for BMW indicates an Internal Transmission Control Module Memory Check Sum Error. This error occurs when the Transmission Control Module (TCM) detects a discrepancy in the memory check sum, which is a value calculated based on the contents of the TCM memory. The check sum error suggests that there may be corruption or data inconsistency within the TCM memory.
BMW DTC P1794 symptoms
Symptoms of the BMW DTC P1794 may include:
- Transmission shifting issues
- Harsh or erratic shifting
- Transmission stuck in a particular gear
- Reduced fuel efficiency
- Illuminated Check Engine Light
BMW DTC P1794 causes
The potential causes of the BMW DTC P1794 Internal Transmission Control Module Memory Check Sum Error include:
- Corrupted TCM memory
- Software glitches or bugs
- Electrical issues affecting TCM communication
- Faulty TCM hardware
BMW DTC P1794 seriousness
The seriousness of the BMW DTC P1794 error lies in its impact on the transmission system’s performance and overall drivability. Ignoring this error can lead to further transmission problems and potential safety hazards. It is advisable to address this issue promptly to prevent any long-term damage to the transmission components.
How to diagnose DTC P1794 on BMW
To diagnose the DTC P1794 on a BMW, follow these steps:
- Use a diagnostic scanner to retrieve the fault codes from the TCM.
- Inspect the TCM wiring harness for any signs of damage or corrosion.
- Check the TCM power and ground connections for proper voltage and continuity.
- Perform a TCM software update if available.
- Test the TCM for internal faults or malfunctions.
How to fix DTC P1794 on BMW
To fix the DTC P1794 on a BMW, consider the following solutions:
- Clear the fault codes using a diagnostic scanner and monitor the transmission performance.
- Reset the TCM by disconnecting the battery for a few minutes and reconnecting it.
- Update the TCM software to the latest version provided by BMW.
- Replace the TCM if internal faults are detected and cannot be repaired.
- Address any underlying electrical issues affecting TCM communication.
How to erase DTC P1794 on BMW
To erase the DTC P1794 on a BMW, follow these steps:
- Use a diagnostic scanner to clear the fault codes stored in the TCM memory.
- Ensure that the underlying issue causing the DTC P1794 has been resolved.
- Perform a test drive to confirm that the transmission operates smoothly without any error codes reappearing.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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