Vibration when braking and warped discs (C3/C4)

Yes, the classic symptom of Warped Brake Discs. In the Citroën range, the discs (especially the front ones) are designed to offer very progressive and efficient braking, but they can suffer from thermal stress.

• Thermal Shock: The most common cause of warping is driving through a deep puddle of water with very hot discs (after a downhill drive or heavy use in traffic) or washing the car immediately after a trip. The sudden cooling alters the metal’s structure.
• Caliper Locked: If the brake caliper’s sliding pin is dirty or lacks lubrication, the brake pad will remain in contact with the disc even when you are not braking. This generates constant excessive heat that eventually warps the disc.
• Dirty Wheel Hub: Often, a new disc is installed on a wheel hub that has rust or dirt. Even if the disc is perfect, it will be “warped” in relation to the axle, causing vibration.

How to Solve:

1. Replacement: For the C4 line (Hatch, Pallas, VTR), ideally, both discs should always be replaced. “Resurfacing” (re-grinding the disc) is not recommended if the disc is already below the minimum thickness, as it will warp again very quickly due to the lower thermal mass.
2. Quality Tablets: Use good quality brake pads. Pads that are too “hard” (with a lot of metal in their composition) generate more heat and accelerate wear and warping of the disc.

Location of Protection (Fuses): If, in addition to the vibration, you feel the pedal “kick” electronically and the dashboard light comes on, the problem may be in the module. ABS.

• Correct Fuse: Check the high amperage fuses in BSM (under the hood)usually the F1 (40A) or the F15 (30A). If the ABS loses power, you will only have conventional braking, without electronic assistance.

Technical Tip: If you feel the vibration in steering wheelThe problem is with the disks. front. If you feel the vibration in seat Whether it’s the car’s brake or the handbrake when pulling it lightly, the problem may be with the discs. rear.