Auto Service World
Feature   May 1, 2012   by Andrew Brooks

Electrical challenge

Servicing a vehicle's electrical systems is an increasingly complex task

he proliferation of computerized systems and networks inside cars has changed forever the nature of automotive electronics, says Dave Crippen, district service manager, Bosch Car Service program. “With the Controller Area Network [CAN], vehicle networking, computers talking on networks, it’s opened a whole different world of problems in the electrical field,” Crippen says. “Now you have communications issues between computers, computers not going to sleep properly and draining power, problems with circuits that look like problems with components … if you’re not a network specialist it’s tough to deal with. You live and die by a scan tool.”

For Mark Sach-Anderson, owner and mechanic at Dave’s Garage in Etobicoke, Ontario, electrical and electronic problems arise from two main causes: corrosion and wire chafing or abrasion. More electronics onboard means more places where corrosion, abrasion and other factors can create problems in a vehicle’s electronic systems. Again, circuit problems can manifest themselves in a variety of ways, and today’s mechanics are increasingly being expected to demonstrate the skills of network specialists in determining whether onboard diagnostics are providing a genuine warning of trouble or are themselves the problem.

Rick Adams, product manager, Customer Care and Aftersales with ACDelco Canada, has also seen the evolution of automotive problems. “An electrical system or device that wasn’t working properly used to be simple,” he says. “It just stopped working – what I call a ‘hard fault.’ Today’s complexity has added what I refer to as ‘soft faults’ to the mix; systems that don’t have any ‘broken’ parts but need to be upgraded, set up, re-initialized or reprogrammed as ‘fixes’ … electrical faults caused by other than the actual system not operating properly.”

Adams echoes Sach-Anderson’s view that the physical wear and tear on the wires carrying electrical loads are playing an ever more important role in presenting ‘problems’ to the automotive diagnostician. “Fretting and corrosion,” he says, “are becoming the most common problems, and there are many OE bulletins surrounding these.” Fretting is where a multi-strand wire is coming apart strand by strand, either due to rubbing, tension or poor material design.

At the same time the overall reliability of components is improving by leaps and bounds, and in the case of starters at least, the vulnerable electronics are now better protected than they used to be. “Most starter motors are integral now,” Sach-Anderson says. “Before, you used to have a solenoid, and you’d replace a solenoid and leave the starter motor. Now they’re both integral. This is a better arrangement. In the past the wires would pull a high current draw in between the two components, but now everything’s encased and sealed up, so the electronics are a lot less open to the elements.”

Alternator technology has also made strides. “Whereas before you’d have a voltage regulator that would full-field them and shut them off, now they’re regulated by duty cycle by the onboard computer systems,” Sach-Anderson says. “So they’re working lot less than they had to before.”

However, the added complexity of electronics and the proliferation of monitoring and control systems have put a premium on diagnosis, which poses a challenge for shop owners. “It’s usually the case with electrical systems that now the diagnostics of the repair far exceeds the repair itself,” Sach-Anderson says. “With the charging system, where before you’d grab a test light and check your field voltage, now you need to get in with a scanner or use a DVM and measure all the duty cycles. In fact, if you put a test light across it you can actually cause more damage than what the vehicle came in for.”

The lengthier processes now required to get a good diagnosis of electrical problems means shops now have to persuade the customer that more time is required to get the job done properly. “We don’t sell parts, we sell time,” Sach-Anderson says. “And to justify somebody’s time at a diagnostics rate of $120 an hour is an extremely difficult sell.”

Eli Melnick, owner of Start Auto Electric of Toronto, agrees. “The typical question is ‘How much is it going to cost to fix?’ When we say we don’t know yet, they ask how much we charge per hour. If we charge $120 an hour to find out what the problem is, they find somebody who charges $85 an hour. Nobody thinks of it in terms of how long it will take you to find a short compared with somebody else. If you take two hours and the other guy takes three, the customer’s paying more.”

Buried costs

Sach-Anderson notes that diagnostics are a “buried” cost, in that customers don’t appreciate the need to find and identify the problem, or the need to purchase the sophisticated equipment that’s needed to interface with onboard systems and figure out what’s gone wrong. “They don’t see we’ve just spent several thousand dollars on the equipment, plus the cost of the software updates from the manufacturer. The reality is that the $120 an hour isn’t necessarily my time. It’s the ‘lease of the equipment to check your vehicle’ is how I put it.”

The battery is the heart of the electrical system, and a problem here can impact many of the vehicle’s other components, with the alternator and starter at the top of the list. The current draw from the starter is always a prime indicator of the condition of the starter itself, but it can also lead back to battery problems, as a battery with lower capacity will tend to increase the current demand from the starter during cranking. Also, if the battery has become sulfated, this will put added stress on the alternator and cause it to fail sooner.

The complexity of today’s electrical systems can allow ‘third-party’ causes to create problems that seem simple on the surface. The fact that the ignition switch in late-model vehicles is connected to the starter through a relay controlled by the electronic control module means that issues with unrelated systems such as security can interrupt the connection, manifesting as a starter problem when in fact the starter is in good condition.

When servicing, it’s important to remember to read the onboard diagnostics before disconnecting the battery, as this will eliminate any codes in the system. Obviously, wiping out trouble codes before they’ve been noted means that potential problems won’t be addressed, and when a failure does finally occur the customer is going to hold the shop responsible.

When replacing a starter or alternator is the only option, the old OEM-versus-remanufactured debate is as strong as ever. The reman option has a lot going for it, provided you use a known and trusted source. “The value of rebuilding depends on where the rebuild is done, and on the quality,” says Crippen. “It’s very important that a rebuilder be checked and verified that they’re doing the job properly – if you get a bad string it’s going to fail in the field.”

Sach-Anderson also stresses the value of verifying quality. “We’ll use remanufactured a lot of the time, but it depends where you’re purchasing from. Make sure they’re reputable and they’re replacing all of the stuff inside the component.”

Remanufactured parts are still the best value for the customer, Melnick says, but now overseas suppliers are able to provide new product often at a lower price than remanufactured parts. While the coverage and quality are still concerns, quality is improving fast, he says. “They want to sell their product, so once a problem is identified they’re the first to fix it,” he says. “So the quality is improving. Really, their competitiveness is incredible compared to what we do to rebuild parts.”