Porsche Diagnostics and Warning Lights in High Wycombe
A warning light on a Porsche can mean anything from a loose connection to a fault that needs attention straight away. We find out which, properly, using PIWIS 4, Porsche’s own diagnostic system, and years of knowing where these cars go wrong.
PIWIS 4: Porsche’s own diagnostic system
PIWIS is the diagnostic equipment Porsche designed for its own cars. Unlike a generic code reader, it talks to every control unit on a modern Porsche, from the engine and gearbox to the suspension, airbags and body electronics. It shows stored and intermittent faults, live data and test routines, and it reads the engine’s over-rev record.
Warning lights we diagnose
- The engine management light, from misfires and sensor faults to air-oil separator problems
- Gearbox warnings, including PDK faults and reduced-power modes
- ABS, PSM and brake warnings
- Suspension and PASM faults, and air suspension warnings on cars that have it
- Airbag, tyre pressure and battery or charging warnings
- Oil and coolant warnings, which should never be ignored
Diagnosis first, parts second
A fault code tells you where to look, not always what’s wrong. Replacing parts on the strength of a code alone is how small problems turn into big bills. We confirm the cause before recommending anything, explain what we’ve found and what it will take to put right, and only fit parts we trust.
Classic and older Porsches
Air-cooled 911s and the older front-engined cars pre-date modern on-board diagnostics, so fault-finding on them relies on experience and hands-on testing. Lawrence has been diagnosing these cars for decades. See our air-cooled servicing page for more.
Common questions
Can I clear a Porsche warning light with a code reader?
You can often clear the light, but not the cause, and a generic reader can’t see most of a Porsche’s control units. If the fault is real, the light will come back.
Is the engine management light serious?
It can be. A steady light usually means a fault that needs checking soon. A flashing light, or a light with the car running badly, means stop and get it checked before driving further.
Do you diagnose faults on every Porsche model?
Yes, from air-cooled classics to the Cayenne, Macan and Panamera. Our Porsche 911, Boxster and Cayman and Cayenne pages cover what we see on each model.
Opening Times
We’re here throughout the week to help with all your Porsche servicing, maintenance, and inspection needs.
- Mon-Fri: 7:30 am to 5:30 pm.
- Saturday: 8:30 am to 12:30 pm
- Sunday: Closed
Got a warning light?
Call us and describe the warning and how the car is behaving. If it’s an oil or coolant warning, or the car is running badly, stop driving and call us first.
