Removing and installing brake light switch on brake master cylinder — AUDI
Removing and installing brake light switch on brake master cylinder on Audi: 5 steps, 1 torque figure.
On the A3 (8P, 2003–2012) the brake light switch is mounted on the brake master cylinder rather than on the pedal box, and it is held by a single bolt. The connector is unplugged, the securing bolt removed and the switch pulled out at the bottom, then lifted out of its retaining tab at the top. Fitting is the reverse, and the job hinges on two small details. The switch has to sit properly in the retaining tab at the top before the bolt goes in, or it will sit at an angle on the master cylinder. And the bolt is tightened to just 5 Nm. Afterwards, confirm the brake lights come on with light pedal pressure and go off when it is released.
🧭 Before you start
Unplug the connector, remove the securing bolt and pull the switch out of the master cylinder at the bottom, lifting it out of the top retaining tab. Fit the new switch so it is fully seated in the retaining tab, then tighten the bolt to 5 Nm and reconnect.
Fits: Audi A3 (8P, 2003–2012)
Don't miss
- Seat the switch properly in the top retaining tab before bolting it.
- Tighten the securing bolt to 5 Nm.
- Check brake lights operate on light pedal pressure and switch off on release, as normal practice.
Written for this job from the workshop steps below · TorqFix editorial.
🔩 Torque settings
Values can differ between engine variants — check the code stamped on your block.
| Torque | Fastener / step |
|---|---|
| 5 Nm (3.7 lb-ft) | Secure brake light switch with specified torque |
ℹ️ Always cross-check the exact figure against your vehicle's factory manual before final tightening — a wrong torque can damage the engine. These values are extracted from workshop data and may not cover every variant or revision.
📋 Procedure
- Unplug electrical connector (1).
- Remove securing bolt for brake light switch (2) from brake master cylinder.
- Pull brake light switch at bottom out of brake master cylinder and lift switch out of retaining tab at top.
- Installation is carried out in the reverse sequence. Ensure proper seating of switch in retaining tab at top.
- Secure brake light switch with specified torque: 5 Nm. — 5 Nm (3.7 lb-ft)
Other AUDI procedures
Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.