A Driving Instructor's Blog

This question crops up regularly in the search terms used to find the blog, but since just before Christmas there has been a noticeable spike. It’s often asked in relation to specific models of car, so I am seeing people repeatedly asking how many turns they need for full lock in Astras, Corsas, Fiestas, and so on.Turning the steering wheel

The obvious solution – to me, at least – would be to sit in the driver’s seat of the car in question and try it. However, if this job has taught me one thing, it is that simple logic is a difficult concept for many people, and you should never assume that what is obvious to you is obvious to your learners.

Full lock is when you turn the steering wheel as far as it will go in one direction. Sometimes even this information is not enough, and pupils need to be told – even shown – what full lock is. It’s not uncommon to have to demonstrate right and left full lock separately, as the pupil hasn’t made the connection that doing it to the left is just the opposite of doing it to the right! On other occasions, I even have to demonstrate the clunk-clunk-clunk you get when the wheel won’t go any further.

I think that some people have so much trouble with this because they see what they’re trying to do as an abstract concept. When I’m doing it, I simply steer as much as I need to in order to make the car do what I want it to do, and if I want the car to turn as much as possible, then I steer as much as possible. However, learners think in terms of “how much did I steer last time?” and not how to make the car do what they want – and that’s where their problems start. That same sort of thinking also explains why the question of how many turns are needed for full lock keeps cropping up.

If I get into a different model of car to the one I normally drive, I never – absolutely never – worry about how many turns I need for full lock. If I need it I just do it – you know: clunk-clunk-clunk, where it won’t go any further. How many turns it actually is is completely irrelevant to me. In my tuition car, the only reason I know how many turns equal full lock now is that I have to keep explaining it. What usually happens is that a learner will merrily flail their arms and break into a heavy sweat when they put full lock on, but when it comes to taking it off they do a wimpy little quarter turn – oblivious of the fact that the car is still swinging out when they start to move. It’s all down to that abstract reasoning, again.Microscopic analysis

Indeed, when it comes to straightening up a pupil will often be staring at the steering wheel, not at what the car is doing, and somewhere in the recesses of their mind a little voice will say that when the Ford logo in the middle of the wheel is the right way up they are straight – with no consideration of the fact that the logo is the right way up when you have one full turn to the left or the right (as well as straight). Sometimes, what I get them to do is count how many hand movements it takes to get full lock on in any direction, then point out that it’s going to need approximately the same number of hand movements the other way to straighten up again (assuming they have the appropriate steering technique).

Another problem that can manifest itself is pupils’ inability to translate steering wheel movement into fractions. The diagram at the top of this article shows a “straight” steering wheel on the left (the white dot at the top helps to illustrate the point). A quarter turn to the right shows the dot moved by 90° to the right (2nd image), a half turn of 180° (3rd image), and ¾ of a turn (270°, 4th image). A further quarter turn results in one whole turn of the steering wheel. Although the idea of quarter turns, or multiples thereof, can be confusing and should be avoided in some cases, it is ironic that those who have the greatest problems with steering can often be helped if they understand the concept of fractions of a turn (well, sometimes – it depends on the pupil). Some instructors go so far as to put a piece of tape on the steering wheel, much as I’ve used a dot in the diagram, though I don’t do that myself – I just refer to the Ford logo.

How do I full lock the steering wheel?

Turn it as far as it will go in either direction. Full lock to the left means steer as far as it will go to the left. Full lock to the right means steer as far as it will go to the right. You’ll know when it has gone all the way because a) it will make a clunk sound, and b) it won’t go any further.

So how many turns IS full lock?

In my car, it is just over 1¼ turns. However, I’ve used Ford Focuses since the MkII model, and back then full lock was almost 1¾ turns. On one of the intermediate models it was just over 1½ turns. I haven’t a clue what it is on a Fiesta, a Corsa, or any other car out there – you’re sitting in one so work it out for yourself.

How many turn to straighten the wheels after full lock?

I can’t believe someone actually asked this – and also wanted pictures to explain it!

You’re going about this all wrong. You need to stop overthinking it. If you look at the steering wheel in your car and turn it to full lock from the straight-wheel position, count how many turns are involved. It really shouldn’t come as too much of a surprise to discover that in order to straighten your wheels up again from full lock, you turn the steering wheel the opposite way by the exact same amount. Conveniently, the logo in the middle of the steering wheel is the right way up when your wheels are straight (it is also the right way up with one whole turn left or right, but you can deal with that).

(18 views today)