Engine and gearbox
Control unit faults, misfires, automatic and manual gearbox operation, sensors, limp-home modes.
Computer diagnostics before buying a car
I come to wherever the car is standing and scan every control unit before you spend your money. That shows not only what is lit on the dashboard, but faults stored in history, traces of recently cleared memory and the mileage recorded inside the modules. I work for you, not for the seller.
We come to the dealer or seller
Every control unit, not just the engine
Plain-language result, right there on site
Computer diagnostics
from 80 zł
Call-out from 150 PLN. The full price is agreed by phone before I set off, so you know the cost before I move.
Call and book a slot
Straight away: what I do and what I don't
I am an auto electrician and diagnostician. I check a car's electronics and electrics: control units, fault codes, module data, the charging and starting system, and in hybrids the battery condition. That is my part of the job and I am good at it.
I do not carry out bodywork or paint inspections: I do not measure paint thickness, assess crash repairs or check suspension on a lift. If you want a full bodywork appraisal you will also need someone for that part — I say so on the phone rather than taking money for something I will not check.
What it gives you
What the computer shows that a test drive never will
A car can drive perfectly and still carry its whole history inside the control units.
The most common sale scenario: fault memory cleared an hour before the viewing. The warning lights go out, the car drives normally and the buyer sees a clean dashboard. But control units store more than the list of active faults — counters, operating modes and traces showing the memory was wiped recently.
Second comes mileage. The odometer is only one of the places a car keeps that figure. In many cars the mileage, or data derived from it, is also written into other modules. A mismatch between them is a signal worth checking before you pay, not after.
Third are the things still building up: a fading battery, an alternator on the edge, a sensor that has not raised a code yet. Invisible on a test drive; visible in the data.
- Active and stored fault codes across every module
- Traces of memory cleared just before the sale
- Mileage and data written into control units, not just the odometer
- Charging and starting system — battery, alternator, starter
- Emissions readiness, i.e. whether the car will pass its inspection at all
- On hybrids — battery condition block by block
Scope
What I scan
Not a single engine control unit, but every module I can establish a connection with.
ABS, ESP and brakes
Anti-lock braking, stability control, wheel speed and tyre pressure sensors.
Airbags
SRS — faults, traces of deployment, sensor condition. One of the first places I look at in a car that has been in a crash.
Electrics and starting
Battery, alternator, starter, wiring. The most common reason for a phone call a week after the purchase.
Emissions and fuel
Lambda sensors, EGR, diesel particulate filter, emissions test readiness before the technical inspection.
Hybrid system
Hybrids add a high-voltage battery — a separate and far more important part. I cover it on its own page.
Pricing
What it costs
Indicative prices for labour. The exact amount is agreed by phone before I set off.
| Service | Price | Notes |
|---|---|---|
| Computer diagnostics | from 80 PLN | Scan of every accessible control unit |
| Hybrid battery test | from 250 PLN | Cell block readings — a separate service for hybrids |
| Call-out | from 150 PLN | Depends on distance |
| Weekend work | +20% | I work Saturdays and Sundays too |
Prices are indicative. The final amount is agreed by phone before I set off — never after the fact.
How it goes
What it looks like
Phone call
You tell me what the car is and where it stands. I give you the price and what I can read on that model.
Call-out
I come to the address where the car is — dealer, car park, the seller's home. Weekends included.
Scanning
Connecting and reading every accessible module. Usually 30–40 minutes.
Explanation
I go through the result without jargon: what is critical, what is worth negotiating, what is normal for that age.
Your decision
You have facts before you pay. The decision stays yours.
From our work
What it really looks like
Footage from actual call-outs — no editing tricks.
Mazda 3 · quick diagnostics after purchase
Mobile diagnostics · working on a SundayThe AD Garage YouTube channel — more diagnostics and repairs in full.
Questions
Common questions
Question not here? Call me — I will answer straight away.
Computer diagnostics from 80 PLN, call-out from 150 PLN. The exact total is agreed on the phone before I set off.
Yes. I come to wherever the car is standing — dealer, car park, the seller's address. The car does not need to be moved.
The scan itself is usually 30–40 minutes, plus a few minutes to go through the result.
No. I work on the car's electronics and electrics. Bodywork and paint appraisal is a separate speciality, and I say so before we book anything.
No method gives total certainty. I read the data stored in the control units and compare it with the odometer — a mismatch is a strong warning sign. Honestly: that is evidence, not a verdict.
Yes, consent is needed to connect to the car. An honest seller does not refuse — and a refusal is itself information.
Yes, and it is a particular strength of mine. In hybrids the high-voltage battery matters most — I cover that on the hybrid battery test page.
Cars and vans of most European and Asian makes. I confirm what can be read on your specific model by phone before we book.
Check the car before you pay
Tell me what the car is and where it stands — I will take care of the rest.
Real repairs, not a brochure
I film what I actually do — including the jobs that did not go my way.