A: Almost never. ECU failure for boost control is exceptionally rare. If a mechanic skips vacuum diagnostics and blames the ECU, find a new mechanic. 9. Final Verdict & Cost Summary | Repair Approach | Success Rate | Typical Cost (Parts + Labor) | |----------------|--------------|------------------------------| | Vacuum hose replacement | 60% | $30 – $100 | | Vane cleaning (on-car) | 80% | $150 – $300 | | Solenoid + sensor replacement | 15% (when done alone) | $100 – $200 | | Turbo rebuild/replace | 95% but overkill | $800 – $1,500+ |
If you’ve plugged a diagnostic tool into a Renault (especially a Laguna, Mégane, Scénic, or Espace from the early 2000s) and seen the code — or the equivalent DF054 — you’re likely staring at a frustrating mix of electrical gremlins and mechanical uncertainty. mot 1654 renault
A: Yes. DF054 is the same code in Renault’s older 4-digit systems. MOT 1654 is the CLIP tool’s display format. A: Almost never
In plain English: The engine’s ECU (Engine Control Unit) commands a certain amount of boost from the turbocharger, but the sensors report that the system is producing too much pressure for too long. DF054 is the same code in Renault’s older 4-digit systems
A second mechanic found a cracked vacuum hose near the brake servo. The tiny leak (3mm split) was causing the turbo actuator to see only 0.3 bar instead of 0.8 bar. The ECU, seeing sluggish vane movement, logged overboost when the system finally caught up.
This article breaks down what code 1654 means, which Renault engines it affects, the common symptoms, diagnostic steps, and permanent fixes. After cross-referencing Renault’s technical bulletins and owner forums, MOT 1654 typically refers to a Turbocharger Pressure Regulation Fault — more precisely, a deviation between the requested boost pressure and the actual measured boost pressure (often a positive deviation or overboost).
Date: October 2023 Reading time: 6 minutes