Mercedes ESP Control Unit Fault: N30/4 Internal Fault (5001)
What the N30/4 code means on a Mercedes-Benz, and your options for the ESP pump and module.
On a Mercedes-Benz, N30/4 is the part number Mercedes uses for the ESP (Electronic Stability Program) control unit. It is fitted to the ESP pump in the engine bay, and it runs the anti-lock brakes, stability control and traction control.
The scan in the photo above, from a Mercedes-Benz C 180 Kompressor (W204), shows 5001: “There is an internal fault in component N30/4 (Electronic Stability Program control unit)”. An internal fault means the control unit itself has found a problem inside the unit, rather than with a sensor or wire outside it.
What you see on the dashboard
- ABS and ESP warning lights
- Brake or brake assist messages
- On newer models, messages such as “Active Brake Assist functions limited”
Is it safe to drive?
Normal braking usually still works, but anti-lock braking and stability control can be switched off. If the red brake light is on or the brake pedal feels different, stop driving and get the car checked.
How it is fixed
We read all the codes first, to confirm the fault is in the ESP unit. Then we repair your Mercedes ESP pump and module, or supply a reconditioned, used or new one. Our repairs come with a 6-month warranty.
WhatsApp us your car model, chassis number and the fault code. A photo of the scan tool screen helps.
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ABS or brake light on?
WhatsApp us the fault code, chassis number and car model. We’ll tell you what we can do.