---
doc-id: SLM-EPB-USR-001
version: 1.0
status: Released
date: 2026-05-12
---

# User Manual — Electric Parking Brake (EPB)

| Field         | Value                                  |
|---------------|----------------------------------------|
| Product       | demo-epb EPB ECU                       |
| Version       | 1.0                                    |
| Date          | 2026-05-12                             |
| Audience      | Vehicle drivers                        |

---

> **Read the important safety information first!**
> Familiarise yourself with the functions before using the EPB.

## 1. What is the Electric Parking Brake?

The Electric Parking Brake (EPB) replaces the classical handbrake. You operate it via a switch in the centre console; the system clamps the rear brakes electromechanically.

## 2. Operation

### 2.1 Engage the parking brake (apply)

1. Bring the vehicle to a complete standstill.
2. Keep the brake pedal pressed.
3. Pull the EPB switch **upwards** (arrow points to the windshield).
4. The red LED on the switch lights up steadily.

You will hear a soft humming sound — that is the actuator motors.

### 2.2 Release the parking brake

**Preconditions** (all must be met):

- Engine is running
- Brake pedal is pressed
- Gear selector is engaged (not in neutral)

1. Push the EPB switch **downwards**.
2. The LED goes out.
3. You will hear a short humming sound again.

### 2.3 Auto-Hold (driver leaving the car)

When you switch the engine off and the vehicle is at a standstill, the EPB engages **automatically after 2 seconds** — even if you didn't operate it manually. The LED confirms.

### 2.4 Hill-Hold on inclines

When stopping on a slope (> 5%):

1. Press the brake pedal — vehicle stops.
2. Lift your foot off the brake pedal — the EPB takes over automatically.
3. The LED blinks slowly while hill-hold is active.
4. On drive-away (throttle + gear engaged), the EPB releases automatically.

## 3. LED indicator meaning

| LED status              | Meaning                                          |
|-------------------------|---------------------------------------------------|
| Off                     | EPB released                                      |
| Steady red              | EPB active (apply / hold)                         |
| Slow blink (2 Hz)       | Hill-hold active or service mode                  |
| Fast blink (4 Hz)       | Fault — visit a workshop                          |

## 4. Display in the instrument cluster

The instrument cluster shows additional text:

| Text                      | Meaning                                  |
|---------------------------|-------------------------------------------|
| "EPB active"              | Parking brake engaged                    |
| "Hill-Hold active"        | Hill-hold is taking over                  |
| "EPB fault"               | Fault — visit a workshop                  |
| "EPB service mode"        | In workshop mode, do not release yourself |

## 5. Emergency mode

If the EPB does not respond:

- **Stationary and won't move:** push the EPB switch downwards several times; if unsuccessful, call breakdown service.
- **Stationary and the EPB does not engage:** secure the vehicle with wheel chocks, contact a workshop.

## 6. Safety information

> **⚠ WARNING**
>
> - The EPB does not replace engaging a gear when parking
> - On slippery surfaces additionally use wheel chocks
> - While the engine is running and the EPB is engaged, do not stand on the brake pedal long-term

## 7. Maintenance

The EPB is maintenance-free. For brake pad replacement, the workshop must activate **service mode** — please do not jack up the vehicle yourself while the EPB is in the active state.

## 8. Revision history

| Version | Date        | Change              | Author     |
|---------|-------------|---------------------|------------|
| 1.0     | 2026-05-12  | First release       | S. Lohmaier|