Posted in: PCM

5 Signs Your Car Needs a New Powertrain Control Module

These days, it seems like just about everything is powered by some type of computer. Complex electronic “brains” often control the inner workings of everything from automobiles to refrigerators, enabling advanced capabilities that would not otherwise be possible. In motor vehicles—at least those built in the last three decades or so—the powertrain control module represents a kind of technological nerve center, ensuring ideal functionality from a vehicle’s engine, its transmission and a host of other essential systems. It stands to reason, then, that a failing PCM is capable of producing a wide range of problems for any car or truck, which means it’s important that any motorist be able to recognize when a replacement has become necessary. Read on to learn more about this mighty module and everything it does to keep you running strong on the road.


Breaking Down the Basics


Auto problems are never any fun to deal with, but as with any complicated system, quickly rooting out the real issue is a vital first step. Determining whether a malfunction exists within your car or truck’s powertrain control module is necessary when common red flags arise, but making an accurate diagnosis begins with a solid understanding of the components in question.


The PCM itself is usually composed of two individual subsystems, known as the engine control unit and transmission control unit. The ECU and TCU interpret information that is provided by many different vehicular sensors, and use that data to maintain peak performance within each of these two crucial systems. Some of the sensors can include those designed to monitor signals from the following outputs:


  • Air intake
  • Coolant
  • Camshaft angle
  • Crankshaft angle
  • Engine knock
  • Mass air flow
  • Oxygen
  • Throttle position


It is also worth noting that certain auto manufacturers do produce some vehicles whose PCMs are more complex, potentially including control of additional systems such as antilock braking and/or traction control, in addition to engine and transmission functionality.


While onboard computer systems are quite common in today’s autos, it remains a fact that many motorists would prefer a return to the days of simpler mechanical construction styles. The computerization of vehicular components can produce a wide range of notable benefits, though this phenomenon also means there are that many more complex systems that are capable of failing at any given time. Unfortunately, a failed control module will just as readily put your car in the shop as a faulty mechanical component, though this fact in itself should indicate just how important automotive computers truly are.


Recognizing Powertrain Control Module Problems


There is certainly no doubt that a PCM is a multi-capable device. It is one that’s responsible for monitoring, and ultimately for controlling systems that range from fuel injection to exhaust and emissions, meaning failure is something you would definitely prefer to avoid. In fact, one of the foremost benefits provided by any PCM is timely reporting of problems that have developed (or are developing) within one of your vehicle’s core systems. This is just one more reason that it’s so important to know what the red flags of potential failure look like.


PCM issues will frequently make themselves known in several common ways, some more easily evident than others. Here are a few of the more typical warning signs that indicate your car’s module is likely to be in need of a repair or replacement:


  1. Engine Performance Issues


If you drive your vehicle with any regularity, it’s probable that you are pretty well tuned in to your car or truck’s usual standard of performance. Should you start to experience a noticeable dip in power, or a sluggish kind of response when you drive, then there is a chance that you’ve got a failing powertrain control module on your hands. Look out also for any evidence of a reduction in fuel efficiency, another commonly observable trait of diminished engine output.


  1. Engine Stalling


Experiencing an engine stall while you’re on the road can definitely be disconcerting, even if you are able to quickly fire your car back up and resume your travels. Such power losses can occur for a number of different reasons, including problems related to fuel distribution, air intake or other mechanical factors. As any or all of these issues can also be rooted in the failure of a PCM, getting a quick and accurate diagnosis is highly recommended.


  1. Starting Failure


While stalling out on the road is certainly a situation you’d rather avoid, sometimes powertrain control problems stop you before you have even made it out of the driveway. Should you find yourself unable to start up your vehicle at all, the problem might be a bit tougher to pinpoint, but as with the rest of these conditions, it’s ultimately necessary to determine whether or not the issue is rooted in your automobile’s core computer system.


  1. Dashboard Diagnostics


Every driver who has experienced issues with a vehicle surely dreads the sight of the “Check Engine” light, an indicator on most dashboards that lets you know when a major system is not functioning as intended. As a rule, it’s best to avoid driving any further than is absolutely necessary when this light flashes on, as you risk doing further damage to any affected components.


A bad powertrain control module can produce many of the diagnostic trouble codes that cause this indicator to activate. Some of the more common DTC numbers associated with such failure can include:


  • Serial communication link malfunctions (P0600)
  • Internal control memory checksum faults (P0601)
  • Control module program errors (P0602)
  • Internal control module KAM errors (P0603)
  • ICM Random access memory error (P0604)
  • ICM Read-only memory error (P0605)
  • Generic powertrain or electronic control module fault (P0606)
  • Generic powertrain module performance fault (P0607)
  • Vehicle speed sensor “A” output error (P0608)
  • Vehicle speed sensor “B” output error (P0609)
  • Vehicle control module options errors (P0610)


Bear in mind that this list is not exhaustive, and that any signs of trouble displayed on your dashboard should be thoroughly investigated. Always ensure the right parts are being serviced in order to avoid bigger headaches down the road.


  1. Indicator Irregularity


Complicating the diagnostic process just a bit further is the fact that PCM problems can actually produce seemingly random trouble codes, often outputting inconsistent reports from start to start. DTCs may even appear to reset themselves or reoccur at random, and the fault codes may be difficult to intentionally reproduce. This is often one of the most obvious signs that problems exist within a powertrain control system, and that a swift inspection is necessary.


The Causes of Failure


Anytime potentially costly repair needs arise, it’s natural to wonder what the initial cause of trouble might have been. In the case of PCMs, it will often boil down to a couple of common culprits. The first is the possibility of a voltage overload, a situation which can occur as result of a short circuit in one of your vehicle’s actuators or solenoids. In either case, it’s crucial that the faulty component is also replaced in addition to servicing the powertrain control module, as voltage issues will otherwise remain and place the new unit at risk.


These kinds of electrical problems can also arise from several different environmental factors. Damage can stem from overexposure to heat, or from overstress due to excessive vibrations over time. Understandably, water poses the greatest risk; if any should enter into a PCM’s housing, corrosion issues can truly begin to wreak havoc. In the event that a vehicle is submerged underwater at any point, as due to flooding, its computer systems are typically considered to be unsalvageable. At this point, full-blown replacement is the only solution available.


The Value of Resolution


By now, it’s probably pretty clear that your vehicle’s PCM provides a number of invaluable benefits. Failure to make necessary repairs not only tends to impact engine performance and efficiency, but it also threatens the viability of your automobile each time you turn the key. Keep in mind that powertrain control modules do dictate functionality for many instrumental components in your automobile, including but not limited to:


  • Air pumps
  • Evaporative emission controls
  • Fuel pumps
  • Radiator cooling fans


Naturally, any driver is going to do their best to avoid overspending when auto problems occur. However, many types of mechanical faults will continue to worsen with time and additional miles traveled, making timely service a high priority. Should you observe any of the common warning signs described above, make the effort to seek out a trustworthy diagnosis. You may even consider investing in an onboard diagnostic scanner, a device that is both an affordable and practical addition to any do-it-yourself mechanic’s toolbox.


Quality Parts at Great Prices


When it comes to auto components, you won’t find better value than when you shop with Importapart. We’re known for our focus on providing high-quality parts and accessories at the fairest prices, and for our commitment to outstanding customer service. Find the replacement powertrain control module that is just right for your vehicle today, and start on the road to renewed confidence every time you’re behind the wheel.