Provided that all your sensors and software are shipshape, these modern cars require significantly less maintenance than older vehicles. Gone are the days of taking your car to your mechanic for a tune-up, to have the timing and carburetor adjusted. That said, computers bring their own set of problems. The tiniest thing goes wrong, and suddenly your Check Engine light is flashing and your radio only works when the vehicle is in reverse.
One of your car’s most important computers is the Powertrain Control Module (PCM). This small computer works in conjunction with your car’s Engine Control Module (ECM) and Transmission Control Module (TCM), to oversee your entire powertrain. Because it’s constantly reading input from sensors and adjusting your engine’s settings on the fly, many mechanics call it the “brain” of your car.
But how do you know that you’re getting the best PCM for your needs?
Today, we’ll take you through the process of replacing your Ford vehicle’s PCM.
What to Consider When You’re Buying a Ford PCM
When purchasing a new PCM, it’s easy to get confused between different models. Many of them look alike, and similar PCMs from the same manufacturer sometimes look identical, right down to the mounting hardware. This makes it easy to install the same PCM on several different vehicles.
That said, it’s important to choose the correct PCM for your make and model. Not all PCMs are the same on the inside, even if they have an identical case. This is similar to any other computer, where the internal components are what matters: the memory, the processor, and the firmware.
The firmware is particularly important for PCMs, since PCMs are programmed to work with a specific make, model, and model year of car. This is even true if there are different versions of the same car. For example, if your car comes with a 3-liter and a 3.5-liter motor, both versions will require different PCM firmware.
And while it’s true that PCMs can sometimes be flashed with new firmware, it’s almost always safer and easier to simply replace your PCM. If you’d like more information on how this is done, take a look at our complete guide to PCM replacement.
When you’re buying your replacement PCM, you’ll want to write down a few numbers from the original, to ensure that you’re getting the best PCM for your vehicle. Make a note of the Service ID and the Ford ID. These numbers should be identical on your new computer.
How Do I Know My PCM Needs Replacement?
Your PCM controls multiple car systems. As a result, you may see symptoms in a variety of your vehicle’s systems. Here are a few common symptoms of a failed PCM.
- Your Check Engine light is on: This can be caused by many engine and electrical problems, from bad valves to failing tire pressure sensors. It may be nothing, but it’s good to get things checked out just in case.
- Your car is hard to start: When your PCM fails, your fuel-to-air ratio can get knocked off-kilter. This can make it difficult for your engine to run, especially while you’re starting it cold.
- Your engine stutters or stalls out while idling: This is another side effect of an incorrect fuel-to-air ratio, and it’s a very common symptom of a failed PCM. Make sure to check your air filter, though, since it can also be caused by a clogged filter.
- Your shifting pattern changes or your car fails to shift: This can be caused by a failure in your transmission’s sensors, as well as by either your TCM or your PCM. It’s a good idea to check with a mechanic if you’re experiencing these symptoms.
- You experience a loss of gas mileage: Once again, we’re looking at a symptom of an incorrect fuel-to-air ratio. It can also be caused by bad timing, as well as by improper shifting.
We’ve written about this in more detail in the past. Read our PCM failure symptom guide for more information.
How Can I Diagnose My Ford PCM?
The most important tool for diagnosing any automotive electronics is an on-board diagnostic (OBD) tool. If you don’t already own one, be warned that they’re on the pricey side. It’s a good idea to ask around and see if you can borrow one, or see if a local job will read your codes for free.
Once you’ve read your OBD codes, you’ll need to look them up to see what they mean. Here are some common codes that indicate a problem with your PCM:
- P0600 – Serial Communication Link
- P0601 – Internal Control Module Memory Check Sum Error
- P0602 – Control Module Programming Error
- P0603 – Internal Control Module Keep Alive Memory Error
- P0604 – Internal Control Module RAM Error
- P0605 – Internal Control Module ROM Error
- P0606 – ECM/PCM Processor Error
- P0607 – Control Module Performance
- P0608 – Control Module VSS Output Error
- P0609 – Control Module VSS Output Error
- P0610 – Control Module Vehicle Options Error
Where Can I Get My Ford PCM Replaced?
If at the end of the day it becomes necessary to replace your PCM, buy from a source you can trust. Solo PCMs carries almost 150 PCMs for Ford vehicles. No matter what your make, model, or model year, we’ve got the best PCM for your specific vehicle.
We understand that this can be a frustrating, intimidating project. If you need expert advice, contact us and we’ll respond with an answer to your query. If you’d like, just give us a call at (888)-848-0144. We hire only the most experienced technicians, and they’re ready to help you find just the PCM you’re looking for.