Once the vehicle has been started, the engine oil pressure, coolant level and temperature, transmission status and fuel level are all sampled by sensors, and their status is reported to the driver. Usually through a general “systems OK” message. Some cars alert the driver only when there is something wrong, illuminating a “check engine” light to tell you that all is not well.
In the old days, engine sensors and instrumentation were very simple. There was an oil light that would illuminate when the oil pressure was low and an alternator light that would come on when the battery wasn’t receiving a proper charge. If something went wrong, the driver was expected to notice an odd reading on one of the gauges.
Today’s vehicles are obviously more complicated. Some of this complication is the result of legislated exhaust emissions and safety regulations. Some of it is due to the vast array of power accessories and luxury conveniences on all but the most basic cars. Digital computers now control engines. And all of these computers rely on fast-acting, reliable sensors. All of these sensors and computers require lots and lots of electrical wires, connections and harnesses. The sheer number of wires needed to control everything from automatic transmissions to power windows is overwhelming. But when things go wrong, it can be even more difficult to figure out where the problem lies.
On the plus side, these digital electronic systems make it easy to constantly monitor vital engine parameters like oil pressure, coolant temperature and exhaust emissions, and report back to the driver when something is amiss. Sensors continually monitor major systems, sending real-time signals to onboard computers. And these computers keep track of everything, alerting the driver only when something is wrong or when it is due for service. More than that, many systems are now required to store information for later access. Service Technicians can plug their own computers into a vehicle and be provided with information to more efficiently diagnose the issue, even if the problem is sporadic.
As complex as vehicle control and monitoring systems have become, they are just a harbinger of what to expect in the future. Hybrid vehicles, which supplement the power from a gasoline engine with an electric motor, require dramatically more sophistication in sensing and control. Some of these systems actually shut the gasoline engine off when it is not needed, and then restart it instantly when its power is required. This process requires a wide range of sensors, all operating properly.
Such dependence upon sensors and electronic systems requires a level of quality and reliability that automobiles have never needed to possess before. It’s a challenge that, if met, will make our vehicles ever more reliable…but it may also make them even harder to diagnose and service when something simple goes wrong.
Want to know more about how to care for your car properly? Learn more about your car by reading our posts!