Transmission Mechanical Failure - First and Reverse
Findings, check these first
- Failed low-reverse clutch or band
- Broken reverse servo or apply pin
- Low line pressure
- Valve body failure in the manual first and reverse circuit
- Catastrophic transmission fluid loss
Standard procedure
- Check the fluid level immediately and do not drive far
- Confirm whether first and reverse engage at all
- Test line pressure
- Inspect for external fluid leaks
- Overhaul the transmission, since mechanical failure will not heal
- Clear the code and retest after the repair to confirm first and reverse engage
Code lookup
Type a code above, or start from a symptom or a common code.
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Sources and review
Review: checked against the recorded source material.
- OBDII.pro: P1784 Ford definition
live reference page (obdii.pro)
Supports: Ford-family meaning for P1784: Transmission Mechanical Failure - First And Reverse
Fetched directly. obdii.pro is a publisher independent of the engine-codes family.
- P1784 FORD Code: Meaning, Causes, and Symptoms | OBD2 Codes
live reference page (obd2-codes.co)
Supports: Ford meaning for P1784: Transmission System First or Reverse Gear Fault Conditions
Fetched directly. obd2-codes.co phrasing matches the engine-codes family, so it counts as one publisher.
Last updated 2026-10-10.
Report a correction for P1784. Include your vehicle, the issue and a source if you have one.
Related Transmission codes
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- P1780Transmission Control Switch Out of Self-Test Range
- P1783Transmission Over-Temperature Condition