Straight and narrow
Here, we look into the latest on steering and suspension systems and how you need to be dealing with them
Published: 30 November, 2020
The steering system has undergone a radical transformation, but tech advancements represent plenty of opportunity for those who are willing to embrace the change.
“For many drivers,” said Julian Goulding, UK Marketing Manager, Delphi Technologies, “the steering of a car starts and stops with the wheel in front of them, but what they don’t know is that while the basics of the steering system remain the same, it’s come on leaps and bounds in recent years.”
Radical
He continued: “Representative of how steering technology has evolved with new components, new materials and new service procedures is the steering angle sensor. While the steering angle sensor was introduced in the early 90s, only recently has it become necessary to reset them after performing a wheel alignment or replacing a component that can alter athe toe and thrust angle.
“Critically, the procedure to do this differs significantly between manufacturers; some vehicles can self-calibrate by having the wheel turned from lock to lock and then centred and cycling the key, some need a quick test drive and others a diagnostic routine. The result is that either way, steering angle reset should now be part of a standard wheel alignment.”
Advancements
What has this meant for garages who are tasked with ensuring that the steering systems of their customers’ cars are always on the straight and narrow?
According to Julian, steering advancements have meant that the aftermarket has had to evolve its servicing offering to fall in line, but the changes can certainly be for the better in terms of increasing revenue streams: “The modern-day steering system is a complex affair, but there’s no need for independents to miss out on the work that’s involved in maintaining it. In fact, they really should embrace any new servicing techniques if they are not to limit their customer base and lose potentially lucrative work to franchised outlets.
“To make it easier for independents, Delphi Technologies transfers its OE learnings to our aftermarket offering, ensuring that garages have quality steering components and, importantly, the technical support to efficiently and competently complete repairs.”
Advancements
Julian went onto say: “Currently, Delphi Technologies’ ever-growing range of steering components comprises over 6,000 part numbers and provides coverage of well over 90% of the UK vehicle parc. Reassuringly, these come with a comprehensive three-year, 36,000-mile warranty and all accessories that are required to undertake a hassle-free replacement.
“It’s the same for our suspension components. Both our steering and suspension offerings provide garages with a quality one-stop solution which allows them to keep abreast of automotive technological advancements, yet still safeguard their established levels of service without the worry of taking a chance on unproven or substandard parts.
“Such a benefit is particularly welcome as we edge into winter. We always see a spike in demand for the likes of steering and suspension parts as these exposed components can all suffer corrosion from extreme weather and salt, while potholes can easily damage a spring or lower suspension parts. Add in normal wear and tear, plus the increased chance of collision damage through icy or slippery driving conditions, and it’s no surprise that demand for these repairs can noticeably rise in the colder months.”
He concluded: “There’s definite potential for workshops to grow business as a result of winter’s impact on a car’s steering and suspension and, importantly, claw back lost revenue from earlier in the year when MOTs were suspended, but they must have access to quality products and even adapt how they inspect a vehicle to take account of the change in season.”
Tie rod end assemblies
Let’s get into some specifics. The steering system plays a key role in vehicles, transforming the circular motion of the steering wheel into a linear motion, which is carried out by the steering gear. “Tie rod assemblies with ball joints are necessary to ensure the driver can steer the vehicle in the right direction,” said Thomas Schwarz, Product Manager at MEYLE. “Because tie rod end assemblies are susceptible to heavy weights and the strain of poor road conditions, MEYLE added 70 new tie rod ends to its range in 2020 including 54 in technically refined MEYLE-HD quality.”
Thomas continued: “The ball pin diameter of the optimised MEYLE-HD ball stud is much larger than that of OE parts. This increases its service life, as the forces applied to the ball are distributed over a larger surface, thus reducing the surface pressure on the plastic socket of the ball joint. This also minimises wear on the ball stud and significantly increases the service life of the MEYLE-HD tie rod end assemblies.
“All MEYLE-HD tie rod end assemblies also feature high-performance grease in the joints, further reducing the wear on these sensitive parts. With this expansion, MEYLE offers more than 700 tie rod ends solutions for a variety of vehicles, including more than 200 in improved MEYLE-HD quality.
“The new MEYLE HD tie rod ends will be joined by new products in the steering and suspension range at the end of the year, with nearly 100 new axial rod solutions in the pipeline, of which more than half are MEYLE-HD axial rods.”
High demand
Thomas added: “Due to the high dynamic loads and forces of driving, tie rod ends assemblies need to be replaced eventually to maintain driving safety. In a video tutorial on the YouTube channel MEYLE-TV, the Hamburg manufacturer demonstrates clean and safe tie rod end installation using a VW T4 as an example.”
Steering and suspension parts also look like they are going to be moving fast for the foreseeable future, partly as a result of COVID-19 and the lockdown.
“With the six-month MOT exemption now over,” said First Line’s Global Marketing Director, Jon Roughley, “workshops need to prepare themselves for the high demand that is there now and will continue into the first quarter of 2021.
“For factors, now is the time to check that their stock levels are ready and they are prepared to cope with this increased demand, particularly for the parts that are regular MOT failures, such as steering and suspension components.
“For technicians, First Line’s full range consists of premium quality products that are relied upon for an efficient and accurate fit. Plus, with all ball joints, link bars and suspension arms, where applicable, being supplied with the necessary fitting components as standard, technicians can also be sure of a hassle-free efficient installation.
“Now, with more and more people back on the road and the MOT extension period over, workshops and factors are working even harder to keep up with demand.”
Natural step
Providers continue to offer new products for steering and suspension systems, including Dayco, which recently introduced a new line of wheel bearing kits.
“The introduction of wheel bearing kits marks a significant, but natural step for Dayco, to add safety related products alongside its established drive systems expertise,” explained Dayco’s National Sales Manager,
Steve Carolan.
“The Dayco range encompasses Generation 1, 2 and 3 technology as well as bearings integrated into the brake disc, reflecting the complexion of the current European vehicle parc and thereby providing workshops with the replacement products they need day-to-day.
“Another strength is Dayco’s longstanding commitment to not only provide technicians with the very best replacement components in terms of their quality, but also to assist them when it comes to their installation. This practice continues with its wheel bearing kits, which, as well as coming complete with all the necessary ancillary items, such as nuts, bolts, pins or circlips, also include fitting instructions and technical tips that can be viewed via a QR Code on the product packaging, to ensure they are installed correctly and in the most efficient manner.”
Steve added: “Naturally, the full range of products are hosted on the Dayco Webcat. This provides users with multiple search routes from make and model or OE/Dayco part numbers, to linked components on related searches.”
Solution
Meanwhile, Schaeffler has introduced a steering and suspension range under its FAG brand.
Schaeffler UK’s Managing Director, Nigel Morgan said: “The FAG chassis component range has been developed from the ground up to benefit from the company’s intelligent repair solution ethos. Ball pins are nitride-treated to maximise longevity, while all exterior surfaces have market leading zinc flake coating technology to resist corrosion. They are further protected by clear thermoplastic polyurethane (TPU) boots with a micro-sealing lip design that adapts perfectly to the ball contour.
He continued: “As well as being unique to the UK market, they are also highly resistant to liquids and mechanical loading, while the transparent material allows the mechanic to see the quality and quantity of the grease inside.”
Nigel added: “Everything we do is geared towards helping professionals carry out the best possible repairs using the highest quality components. The addition of the FAG steering and suspension range is therefore a significant development, allowing us to provide workshops with a viable alternative from a trusted supplier, along with the market leading workshop support that we offer with every Schaeffler product.”
- Morris Lubricants launch new Racing Ambassador video series
Morris Lubricants Racing ambassadors Guy Martin, Lydia Walmsley and Dave Jenkins have joined forces for the first time in a six-part series of exclusive video interviews.
- Forward to the rear: Schaeffler partners with Bosch for rear wheel steering
Schaeffler is teaming up with Robert Bosch Automotive Steering to expand its intelligent rear wheel steering (iRWS) portfolio.
- Process, process and more process
People ask me what made the difference this year when I went from being a Top Technician finalist to a Top Technician winner, and my answer is my process. I have worked hard since last year’s final, refining my process, and learning from my mistakes and it thankfully paid off this year. This article highlights the importance of a great process not only in Top Technician, but also in everyday working life, and how a fault, which at first may seem overwhelming, can be simplified and confidently fixed.
The week after winning Top Technician, a 2016 Ford Ranger was booked in for me to have a look at from another garage. The garage’s complaint was that multiple warning lights were present on the dashboard along with multiple warning messages, the power steering was heavy and the indicators and windscreen washers didn’t work from their respective stalks.
As with every job, the first step of my process is to interview the customer and gather as much information as possible. When I questioned the garage owner, he said they had just completed fitting a galvanised chassis. He explained that the vehicle had been fully stripped and rebuilt in the process, and since the rebuild, warning lights, messages and other complaints were now present. The next step was to confirm the fault. Upon starting the vehicle to bring it into my bay, the complaint was verified. The engine management, traction control, anti-lock brake and airbag warning lights were illuminated along with multiple different messages, one of which was a steering assist malfunction warning (see fig. 1).
Complete picture
I then carried out a global scan of the vehicle to get a complete picture of what faults were present and also to see what modules were or were not talking to the scan tool (see fig. 2).
Straight away we could see that multiple modules could not communicate with the power steering control module (PSCM) and restraints control module (RCM). It was also noted that there was a communication issue between the body control module (BCM) and the steering column control module (SCCM).
As the instrument panel cluster (IPC) communicated and reported stored fault codes, I knew it was more than likely a historic fault code which wasn’t related to the issues present. Attempting to communicate directly to the PSCM, SCCM and RCM with the scan tool all returned a ‘no communication’ message, so we knew we were dealing with hard faults that were currently present. Following my process, I decided the next step was to do some research on this particular vehicle using Ford ETIS which is Fords online information portal. This allows me to access wiring diagrams, connector locations and anything and everything related to the vehicle in question. As many a clever man has said, “if you don’t know how it works how can you fix it?”
Thinking of possible causes, I decided to study the wiring for the PSCM and RCM, how the indicators and windscreen washers work and a network topology to allow me to see how all the modules communicate to each other and the diagnostic scan tool.
It was found that the steering column module controlled the indicators and washers and sent the message to the BCM to activate them. As the SCCM wasn’t communicating it now made perfect sense why those functions were not operating. Next, I found that all three modules worked on the high speed can data bus and all were powered by fuses. All the related information and diagrams were printed out and taken to the vehicle so that a test plan could be drawn up and executed.
Plans within plans
Before writing up my plan, I made a visual inspection of wiring under the bonnet and underneath the vehicle. Having had a major overhaul, something as simple as there being a connector left unplugged could cause some of if not all the faults present with this vehicle. Everything looked ok, so I laid out my wiring diagrams and proceeded to write a plan. My plan was to test the fuse for each of the modules to see if it gave me direction, then if all was ok I would look at the communication wiring and how the modules at fault linked into each other and the rest of the vehicle.
All three fuses tested fine so it was onto seeing if there was a common link. Looking through the topology, I found a page which had the PSCM and RCM joined by two connectors. This is where technical information is a must, as dealing with a fault like this it can be very easy to dive in full speed. I don’t want to go straight to a module, for example the RCM, and remove half the interior of the vehicle to find all is ok there and have to spend time reassembling everything! I speak from experience here, and I am sure some of you reading can relate to this.
Diagnostic direction
ETIS showed one connector inside the nearside front wheel arch and the other in the location of the bulkhead of the vehicle. This meant I could test the network without removing anything, saving time and gaining diagnostic direction. I inspected visually to see which of the two connectors was the easiest to access and it was the connector in the nearside wheel arch. Visually the connector looked correct and looked to be correctly latched. However, I decided to double check and upon squeezing the two sides together and audible click was heard meaning the connector was open (see fig. 3).
I then decided to scan the vehicle again to see if this had made any change and every module now communicated and it was also noted the dashboard warning lights had disappeared. I cleared all the faults codes in the vehicle. None returned, and the dashboard now had no messages or warning lights illuminated. The final checks proved the steering assistance now worked correctly and the indicators and washers operated completing the fix.
In the end then a fairly simple fix once it was established how the system worked and where everything was located but without the correct information and a well polished process this job could have taken a very different, and perhaps longer, turn.
- Steering you right?
Picking up from my topic and opinions on autonomous vehicle control last month I think it reasonable to explore the very technology our safety is to be placed.
When considering the most challenging aspect of autonomous vehicle control, we must look to steering and stability correction. My references are limited to the Volkswagen Group, however most manufacturers now share similar drivetrain and chassis technology.
Steering assist
These systems have evolved over many years in what I term modular development. Steering assist is such a system. Steering assist is directly proportional to driver input force, the steering torque sensor g269 detects rotation, the steering angle sensor g85 provides angle and rotation acceleration.
Responding to this data the control module j500 calculates the required assistance from the power steering assist motor v187. When parking, a low or zero vehicle speed combined with a rapid steering input provides maximum assistance. During driving additional data relating to environmental conditions, urban or motorway, modifies the appropriate assistance.
One of the first problems to overcome was return to neutral or zero steering angle. This is activated with a reduction in force on the torsion bar, whereby the rate of return is also a function of environmental influences. The dual steering angle sensor is comprised of a LED and photo electric diode.
The steering torque sensor operates on the magnetic resistance principle. Failure results in a gradual reduction in assistance. The asynchronous brushless motor provides up to 4nm of assistance. Once again emphasis should be directed to programming and adaptive correction via e serial platform.
Stability & proximity
When introducing vehicle stability dynamics, even more data is required: An accelerometer as well as yaw and pitch sensors will complement existing input requirements. Enhanced and shared functionality with ABS enables the braking system to support vehicle control through corners by applying a control force through the rear brakes.
We now need to consider the vehicle proximity control system; the system employs an ultrasonic sensor to monitor and determine the environment. However, this interim system has several critical shortcomings, especially due to its narrow detection field and inaccurate position calculation regarding other vehicles and obstacles. The next modular enhancement introduces side or blind spot monitoring or side assist. This system also has limitations with range and vector limitations. Although operating on a high speed can network, it operates on a master slave principle, for example; slave units only transmit data and diagnostics on demand from the master module.
It is of note that the vehicle now relies on no less than 13 control modules, with predictive position algorithms. Later evolution will include optical, video, ultrasound, infrared and laser. Optical lane assist which is mounted on the windscreen requires considerable coding and calibration, notwithstanding windshield replacement, so much for off-site repairers.
Calibration & correction
Calibration requires determination of the camera orientation, the exact installed location, the height at which the camera is installed and three orientation measurements. This is an electronic function as no mechanical adjustment is provided. Therefore any change in tyre, wheel diameter or suspension repair or modification will invalidate this system accuracy, including fault memory errors.
We now move into the era of de-coupling direct driver steering input. This system allows computer correction of steering angle. For example, with a loss of driver control, ESP can introduce a counter steer input to regain control. This system is intended to maintain the maximum static traction between the road surface and tyre. Should this be insufficient to maintain a safe curve radius, the ABS can be employed to help recover the vehicle attitude.
The system can carry out actual steering angle correction while the driver maintains a different steering wheel input, such as on snow, ice, or on flooded road surface conditions. In order to facilitate this function, a mechanical flexi-coupling is mounted in the upper steering column. The outer has 100 teeth, with the inner posessing 102. They can rotate together as one with direct driver input command or can rotate at a different angle disengaging driver direct input control.
In effect this system still complies with statutory requirements as having still a de-facto fail-safe mechanical connection between driver and steering mechanism. Therefore is still level 0 status, in terms of autonomy.
At this point we are a million miles from even level 2 or 3 autonomous control. Level 3 allows for the driver to release physical contact with vehicle controls yet remain available and alert in case of system failure. Please make your own mind up. However, I’m not for turning!
- No self control?
Having witnessed the growth of passive driver assist systems and the intent to move towards fully autonomous vehicle control, my topic this month is to raise both thought and debate towards the implications. My first intention is to separate assistance from autonomy.
I fully support assistance as it provides a safer environment for the driver to concentrate on vehicle control. Many of these systems have been available for a very long time, including possibly the very first, power steering and power windows.
ABS to power steering
Anti-lock braking systems (ABS) are, I think, an excellent example where drivers may be misled as to the safety improvements. However, the laws of physics still apply, and the co-efficient of friction and kinetic energy will always dictate the retardation distance and vector. Obvious enhancements to ABS work as a fully integrated system, including dynamic chassis stability.
Early variants simply monitored the wheel speed sensor frequency, reducing the engine throttle angle to reduce torque through the driving wheels when a significant differential existed. Recent additions now include variable geometry anti-roll bar and adjustable rate shock absorber damping with self- levelling.
Evolving in parallel with these systems, and this is where there is an arguable transition from passive to active or automatous control, is the steering system. The introduction of power steering does have great advantages in reducing driver fatigue and improving mechanical response to steering wheel input. The next evolution was variable rate steering assist, whereby the assistance is proportional to steering angle and road speed. with the evolution of brushless motors and highly accurate position sensor technology, steering systems now offer corrective suggestion to the driver via a subtle torsion bar within the upper steering column. Should the driver resist this small force the system will disengage leaving the driver fully in control.
I am choosing to ignore for the moment fully autonomous steering control as it embodies a whole array of additional control input requirements. This allows me to focus on some of the more peripheral driver support systems which I do fully endorse. Matrix vehicle lighting control is possibly one of the best safety improvements. This enables full beam lighting always, yet avoiding oncoming vehicle light stray. Smart cruise control is also especially useful on motorways in uniform traffic conditions.
Compliance
The next group of driver assist starts to cross the boundaries of assistance, this is due to the introduction of long- range transmitters and receptors, lane divergence, and vehicle proximity awareness. This technology does of course lend itself to other previously mentioned systems.
There should be a very sobering pause at this point. To maintain system integrity and accuracy from the above systems a little thought should be given to the almost non- existent function called calibration.it is critical. If you fully consider the implications of everyday servicing and repairs that affect these systems, compliance is the responsibility of the repairer. This means you.
This is the point where I cannot avoid the transition towards full driverless autonomous control. Due to several critical considerations, technical compliance, political compliance, legal compliance, and public acceptance, it is to be rolled out in five steps over several years. Ford recently suggested it could be implemented by 2021, with level zero full human control, to level five where the human has no input responsibility.
What of the globe’s biggest commerce giant’s? Intel has just purchased an Israeli autonomy tech company for $15 billion. Google has spent a modest $30m, and Facebook is in it too. All hellbent on convincing us of the benefits in total vehicle automation. Given their past and current dishonesty, self-interest, and responsibility avoidance you can bet it all going to be a financial beartrap.
However, my personal feelings are more complex. Humans has evolved over many thousands of years by overcoming and controlling a multitude of challenges. It has enabled our brain and cognitive functions to develop to incredible levels. Imagine then, being trapped in an autonomous container with absolutely no functional requirement. What will you do by way of brain stimulation or choices. I accept traffic jams are worst than toothache, but driving is a socially shared experience. Think of the simple activities that release endorphins, such as cycling and walking. Why? because of the brain stimulation and cognitive responses, a form of achievement.
If you must have total autonomy for your travel requirements, then public transport is available now. My acid test for the techno maniacs out there is, given that the technology is currently available and has been proven over several years, would you choose to fly in an aircraft with no pilot? Remember that even in autopilot there are teams of humans constantly monitoring the flight path and technical systems.
Credibility
I’m not ignorant of the accident statistics that give credibility to automation, if that was the true motivation, then smoking and alcohol would be banned tomorrow as they kill and maim an awful lot more.
It has been suggested that our home environment would be improved as our car could drop us off and then park its self in a less congested place, so if you live in central London your car could end up in a South Downs village. On a more sinister note, if an autonomous vehicle faced with an inevitable collision from a oncoming car, would it mount the pavement and choose the mother with a pram as the better survivable outcome for its occupants?
The very best qualities of life always come back to interaction, be it with other people, pets or machines, what next? When do machines decide we are the redundant component? Disagree, or debate, but don’t accuse me of not embracing technology, I have spent my life trying to master it.
