The Powertrain manage Module (PCM) is the computer that controls many of her Jeep’s vital systems. The PCM controls the engine timing, the fuel to air ratio, the transmission, and the anti-lock brakes, along with dozens of various other smaller functions.

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When her PCM fails, the can reason you to lose fuel efficiency and possibly fail her state’s emissions inspection. That can additionally lead come backfiring, challenge starting the engine, rough shifting, and rapid wear and also tear on crucial engine components.

Common symptoms of Jeep PCM Failure

Because her PCM controls numerous of her car’s systems, there space a huge number of possible symptoms. The most noticeable is if your password scanner is reading any type of code that begins with “P06”. These codes all identify particular PCM problems.

Other common symptoms include:

– The check engine irradiate is on– her engine stutters or stalls– Gas mileage has inexplicably gotten worse– your Jeep is moving erratically or seemingly in ~ random– her Jeep has challenge starting

The main reason world spend so much on PCM fix is that plenty of people, even professional mechanics, frequently misdiagnose PCM difficulties as engine or transmission issues, and also attempt i have lot of money repairs to those systems. You can buy several PCMs for the expense of rebuilding one transmission.

Worse yet, rough shifting and poor engine timing can cause damage end time, which means that the much longer the problem with her PCM walk undiagnosed, the much more you’re most likely to end up spending on repairs down the road.

If she experiencing any of these problems, the a great idea to have your password read before spending a the majority of money on mechanically repairs. In ~ the very least, you’ll eliminate a possible cheap fix option. At best, you’ll be able to repair or replace your PCM prior to anything else it s okay damaged.

Diagnosing the Problem

Even if her PCM is sending a error code, the trouble may no be through the PCM itself. It might be with the wiring harness. Execute a visual inspection of the wiring, and replace any corroded contact or frayed wires. If every little thing looks great from a intuitive standpoint, monitor up with a multimeter to make certain you didn’t miss out on anything.

Another typical problem is if her battery ground has shorted the end to the vehicle’s frame. Check your battery contact themselves, too. Short voltage is a cause of countless PCM faults.

Beyond that, it’s a great idea to perform other diagnostic procedures based upon the precise error password you’re reading. We’ve written separately around several of this codes, in ours PCM fix blog.

One typical problem that affects Jeep PCMs – particularly PCMs for the Jeep grand Cherokee – is negative soldering top top the 5-volt strength connection. If all other tests have actually failed, girlfriend can try re-flowing the solder. We’ll walk over this procedure in the next section.


Repairing your PCM

Repairing a damaged PCM is difficult for anyone who isn’t proficient with soldering on a printed circuit board. In ~ Solo Auto, our dedicated technicians have the right to repair your PCM and also mail it ago to you in ~ 24 come 48 hours. Once you letter in her PCM, ours technicians will certainly assess the symptom of her module, calibrate the codes, and also conduct an internal and external inspection. As soon as repairs room made, we’ll test the unit to ensure its working correctly, upgrade the programming codes, and retest the PCM prior to mailing it ago to you.

If friend are proficient in these kinds of repairs and are willing to take it the risk and also make the effort yourself, here’s what you’ll have to do.

First, you’ll need a 60/40 rosin main point solder. It must be rosin core, not acid core, due to the fact that acid core solder can damages the circuit plank itself. You’ll additionally need DeoxIT, or a similar non-corrosive call cleaner.

Remove the two tiny screws in her PCM cover, and also carefully pry the closeup of the door tabs open. Remove the little cover, and set it come the side. Then eliminate the larger cover, and turn that over. Top top one side, you’ll check out an electric connector that’s soldered on. Clean off any type of potting compound, and reflow the solder, using as little brand-new solder as vital to carry out the job.

Make sure the solder operation from each pad to the connector for that pad, there is no touching any type of other connectors and causing a short. Be really careful when you’re law this. Any damage to the copper circuits will certainly permanently ruin your PCM.

Next, clean all the contact with call cleaner, and also reassemble her PCM. Occasionally this an approach doesn’t work, but it’s reliable in the bulk of cases. If her PCM still no work, you’ll need to replace it.

Replacing your PCM

When you’re trying to find a replacement PCM, it’s important to keep in mind that PCMs are programmed because that a certain make and also model of vehicle. If you drive a 2007 Jeep Liberty through a 3.7-liter V6, girlfriend can’t usage just any kind of PCM. Friend can’t usage just any kind of Jeep PCM replacement. You need the PCM for that precise car. Solo PCMs has more than 100 Jeep PCMs because that sale, so girlfriend can find exactly the variation you need.

Most PCMs are plug-and-play, therefore installation is simply a matter of disconnecting the strength supply, removing the old PCM, and also installing the brand-new one. If you’d like a much more detailed explanation, our PCM replacement guide defines the process.

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How have the right to We Help?

If friend have any questions about your PCM fix or replacement, contact us on our website, or contact us in ~ 888-848-0144. specialization in automotive computers, and our technicians are constantly willing to share their expertise.