Car diagnostic guides: comparisons and how-tos

How-to

How to register a new battery with a diagnostic tool

On cars with stop-start, the control unit adjusts charging to the battery's age. Fit a new one without telling it and it will keep charging it...

October 28, 2026 · 2 min read

How-to

How to calibrate the steering angle sensor (SAS) with a diagnostic tool

After a wheel alignment or a new steering rack, the ESP light can come on because the car doesn't know where the centre of the steering...

October 28, 2026 · 2 min read

How-to

How to bleed the ABS with a diagnostic tool

If air has got into the ABS unit, a normal bleed won't do. The diagnostic tool opens the valves and runs the pump to push it...

October 28, 2026 · 3 min read

How-to

Live data on a diagnostic tool: which values to check and what they mean

Fault codes tell you what the control unit has seen. Live data tells you why. These are the values worth checking first and how to read...

October 28, 2026 · 3 min read

Fault code

How to read and clear fault codes with a diagnostic tool

How to run a full scan, read each code with its description and freeze frame data, and clear faults only when the time is right. Plus...

October 28, 2026 · 3 min read

How-to

How do you update an iCarsoft diagnostic tool?

Tablets update themselves over Wi-Fi and handheld tools from a Windows PC. Here are both methods, how long free updates last and the most common errors.

October 28, 2026 · 3 min read

How-to

How do you connect a diagnostic tool to your car, and where is the OBD2 port?

Where to find your car's OBD2 port, how to plug the tool in without any fuss and what to check when it won't communicate. The first...

October 28, 2026 · 5 min read

How-to

How to program TPMS tyre pressure sensors

When you change a tyre pressure sensor, the car won't recognise it until you program it and run a relearn. We explain the three methods (clone,...

October 21, 2026 · 4 min read

Fault code

How to clear the engine warning light with a diagnostic tool

Clearing the engine warning light takes a minute; what matters is knowing why it came on. We show you how to read the code, make sense...

October 21, 2026 · 4 min read

How-to

How to regenerate a diesel particulate filter (DPF) with a diagnostic tool

If the particulate filter warning light comes on, a forced regeneration can clear it. We explain when it makes sense, how to do it safely and...

October 21, 2026 · 3 min read

How-to

How to release the electronic parking brake to change brake pads

With an electronic parking brake you can't just push the piston back: the calliper motor has to be retracted with a diagnostic tool. Here is how...

October 21, 2026 · 4 min read

How-to

How to do an oil service reset with a diagnostic tool

You have changed the oil and the dash still says the car is due a service. Here is how to reset the service interval with a...

October 21, 2026 · 4 min read