Power loss when switching on the air conditioning — what to check
A practical guide: from symptoms through common causes (compressor, belt, electrics, fuel, cooling) to safe checks and workshop diagnostic steps.
eCarService · Driver Academy
Car care guides for drivers
Learn what a warning light or worrying symptom may mean, what you can check safely and when you should stop driving.
Symptoms and possible causes Step-by-step diagnostics Practical driver knowledge
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guides to help you prepare for a conversation with a workshop.
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Latest guides
Knowledge that helps you understand your car
Learn about the possible causes first. Choose a location once you are ready to book a visit.
Diagnostyka7 min
How to prepare your car for diagnostics to make finding a fault easier?
A practical guide on what to do before a workshop visit to shorten diagnostic time and increase the chances of correctly identifying the cause of a recurring symptom.
Engine and emissions5 min
DPF warning light and power loss — what to check?
The DPF warning light, a diesel particulate filter message or a noticeable loss of power after many short trips usually mean the filter has started to fill up or that regeneration has failed. The symptom alone does not yet tell whether it’s just the driving style or also the EGR, the injection system, pressure sensors or the exhaust system itself.
Petrol smell in the car — fuel or EVAP?
A petrol smell shouldn't be ignored: sometimes it's just transient vapour after refuelling, but it can also signal a fuel leak or a problem with the EVAP system. We explain when you can cautiously drive on and when to stop and get a diagnostic check.
Engine and cooling5 min
Radiator fan runs after engine off — is it normal?
The radiator fan running after engine shutdown doesn't always indicate a fault. We explain when it's normal cooling and when it points to a problem with a sensor, relay, coolant or control and requires diagnostics.
Engine and electrics4 min
Diesel struggles to start cold and smokes — what to check?
If your diesel cranks longer in the morning, starts unevenly or emits white smoke after start, don't assume a single fault. This combination of symptoms can point to a weak battery, worn glow plugs, fuel supply issues, an intake leak or an engine control fault.
Engine and emissions5 min
Check engine light and rough running — EGR or intake?
If the check engine light is on and the car starts to run unevenly at idle, vibrate or sometimes jerk on light throttle, don't assume a single fault. This set of symptoms often fits an EGR issue, a dirty intake, air sensors or a leak in the engine control system…
EGR cooler: coolant loss and exhaust smell
If a diesel loses coolant and there is a sweet smell, exhaust odour or light white smoke, don't assume a single fault. Those symptoms can fit a leaking EGR cooler, but other cooling, intake or exhaust parts may behave similarly.
Engine and emissions4 min
AdBlue: fault and restricted start — what to check?
An AdBlue message, engine warning light and a restricted start notice are warnings not to ignore. The car may still run, but usually only for a limited time and without any guarantee it will restart after being switched off.
Engine and electrics6 min
Start‑stop not working: battery or charging?
Start‑stop not working doesn't always mean a fault. The system often protects the battery, but with poor starting or warning messages it's worth having a diagnostic check.
Driving safety4 min
Fuel smell in the car: is it safe to drive?
A fuel smell can be temporary after refuelling, but a persistent odour in the cabin, under the bonnet or a wet patch beneath the car requires a prompt check.
Exhaust smell in the cabin: can you drive?
If you smell exhaust in the cabin, don't treat it as a minor nuisance. If headaches, dizziness, nausea, weakness, confusion or chest pain appear, stop driving, ventilate the car, get out in a safe place and do not continue exposure.
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