P0603 Code 7.3 Powerstroke – [Meaning, Causes & Fixes!]
Here’s a scenario, Check Engine Light illuminates. With the help of an OBD2 tool, you get to know its P0603. Along with the code, the 7.3 engine may leave you with other troubles like start problems or inconsistent speed.
So, what does the code signify?
P0603 Code 7.3 Powerstroke shows up when PCM fails to store and use its data from KAM needed to boost driving performance.
Several issues can get you the alert. Since it’s pretty frustrating, I’ve tried to put all the detail here to help you know what causes them and how to fix them.
what dose P0603 Code 7.3 Powerstroke mean?
P0603 is a Diagnostic Trouble Code for “Internal Control Module Keep-Alive Memory (KAM) Error”.
It appears when our vehicle’s control unit can’t use the information stored on the memory chip failing a self-test. Let me make it easier to understand.
How Do PCM And KAM Work?
When we get a new vehicle, its PCM comes set with default settings from the factory to control several systems. As we start using it, the computer makes different tweaks so the internal system functions optimally. However, it doesn’t alter the settings all the time. Instead, it saves and stores the info in KAM that works to tailor and sync the settings with our driving pattern.
This memory chip is what keeps several contents related to our driving habits. It saves settings and data regarding-
- Fuel adjustments
- Transmission
- Ignition
- Injection timing
- Adaptive shifting
- Idle trims
- Anti-locking brakes.
Just like any engine PCM, the one in 7.3 Powerstroke works with the data continuously. It constantly updates and runs a self-check as we drive our vehicle to make up for any changes in driving conditions, environment, and damage to the internal system.
Whenever there’s an error in KAM, the computer can’t use the info. In such situations, it starts running different diagnostic tests to get back the saved data. When it fails after several attempts, it sets to default and triggers a DTC P0603.
6 common Symptoms Of P0603 Code 7.3 Powerstroke
Along with P0603 Code, some signs indicating PCM and KAM error in 7.3 Powerstroke make it obvious. Let me add 6 common symptoms of P0603 problems.
Warning Lights Activated
An obvious way to detect DTC P0603 is the Check Engine Light. It illuminates when there’s an internal problem. You use an OBD2 scanner to find out the core. In case the PCM or KAM is the culprit, it throws that specific trouble code.
Besides, Service Engine Soon Light (SESL) may turn on. It activates if ignition coils and/or spark plugs fail which affects PCM or KAM.
Start Issues
PCM ensures every system and part in the vehicle works properly. It also includes ignition timing. In case it gets disconnected or damaged, spark plugs won’t ignite air-fuel mixture. Consequently, you experience issues with starting along with the KAM error. It may either cause a rough or no start at all.
Along with PCM, faulty or loose battery terminals can leave similar symptoms and trigger a P0603 trouble code.
Engine Stalling
A defective or disconnected battery and PCM can cause KAM error leading to engine stalling.
When battery malfunctions especially due to corrosion or becomes loose, the alternator works harder to ensure the engine runs. It also puts extra stress on the alternator straining the engine. As a result, vehicle stalls out.
If PCM failure is caused by corrosion, faulty battery, and other problems, it fails to supply correct fuel mix. When engine gets less fuel, it ends up stalling.
Misfires
This happens when KAM gets affected due to defective wiring, control module, and/or battery.
All the parts play role when it comes to keeping the engine running. Faulty spark plugs tend to delay the effect of combustion. Bad computer mishandles fuel mixture. And faulty batteries affect spark plugs. These problems can cause engine misfires along with P0603.
Irregular Speed and Idling
Worn-out battery, PCM, and/or wiring can be the source of rough idling and speed. Not only do they affect the memory chip but also the performance of vehicle.
When the battery or control module is bad, it doesn’t supply enough power to the engine. In case it’s spark plugs, it leads the fuel to be burnt at an inconsistent rate. All this results in irregular idling and acceleration.
Random Shifting
A common cause of unpredictable shifting is worn-out circuit in PCM. When it’s affected, the computer may send poor data to TCM. And consequently, the vehicle fails to shift gears properly.
Sometimes, corroded battery terminals can cause random shifts. Due to damage, transmission doesn’t get enough power to make the gears function on time.
troubleshooting guide for P0603 Code 7.3 Powerstroke
Different problems with the car control module and batteries can lead to P0603 Code In 7.3 engine. Here’s a table with some of the common causes and ways to fix them.
| Problem | Easy Solution |
|---|---|
| Loose connections | Make them tight |
| Worn battery terminals | Buy a new battery |
| Dirty battery | Clean it. |
| Low battery | Recharge it |
| Software problems | Reprogram, update, or reset the control module |
| Damaged PCM or KAM | Repair or replace with a new one |
| Malfunctioned wiring | Repair the wiring or replace the circuit board. |
The real problem lies within battery terminals or control module that throws a P0603 Code in 7.3. Let me explain all the issues separately and guide you to the solution.
1. Battery Problems
Any problem with the battery terminals can leave a DTC P0603 in 7.3 Powerstroke. No matter whether they are loose, corroded, or damaged, such defects can reset KAM. Besides, low battery charge can throw the same issue. These all force PCM to set back to factory settings and send the error code.
Fix
First, remove the battery and check for any sign of corrosion. To get rid of the rust, try to clean and neutralize it with baking soda. And fit it back into place. This should clear the code.
But if they are damaged, I advise you to change the battery.
Then again if it looks good, the connections might be loose. For that, you have to tighten it properly.
However, in case everything is working well, check the interior of battery. Use multimeter to see the voltage. Recharge the battery in case it runs low.
2. Software Problems
A mismatch or bug in software or outdated programs can create issues in the computer and engine system. Result, it generates P0603 trouble code in 7.3 engine. This can also lead to failing PCM if you don’t fix it on time.
Fix
Depending on the problem, try to reprogram or update the software using a scan tool. If it doesn’t solve, then I suggest you flash the firmware and set the computer to default settings.
3. Damaged PCM or KAM
Both PCM and KAM can fail due to thermal stress, excess vibration, water damage, short circuit, and corrosion. When they malfunction, they can’t control the system and process the data from storage. Consequently, it shows P0603 error code.
Fix
In case the PCM or KAM isn’t completely damaged, then repairing the device may help. Have the experts run several tests to detect the main problem and fix it. If the device fails, then get a new one.
4. Malfunctioned Wiring
In case the wire to the memory chip and control module gets damaged, it can generate P0603 code. The defects may happen due to short or open circuits and blown fuse. Mostly, water and corrosion are the culprits. However, it can also occur for other reasons such as when you deal with the wires. When wires malfunction, it breaks connection between PCM and KAM and data can’t be recorded.
Fix
To deal with this, check which of the wiring has gone bad. I suggest you take an expert’s help to repair the wires unless you’re one. If the damage is beyond repair, then just replace it.
The same is for any wiring connected to PCM, especially spark plugs or ignition systems. In case you notice any sign of damage, repair or replace depending on problems. But make sure to check the coil packs and plug wires. You can start the engine and inspect it. If there’s any spark coming from ignition, then wires may have issues. The solution: repair or replace.
Then again, contact a technician if you’re an amateur.
How To Clear P0603 Code In 7.3 Powerstroke?
The following steps can help you clear P0603 Code In 7.3 Powerstroke.
- Charge batteries that run low.
- Clean the battery terminals.
- Make the connection tight.
- Check the charging system.
- Change faulty batteries, KAM wires, spark plugs, and/or PCM.
- Update or reset the software programs.
- Run your 7.3 engine for around 30 seconds.
How Much Does It Cost To Repair P0603 Code?
P0603 Code repair may take a few dollars to over $1,700 depending on the problems.
- Battery cleaning: $5 to $20. Cost needed to buy supplies like baking soda or battery terminal cleaning tool to remove corrosion.
- Wiring replacement: $50 to $1,700 and $67 to $84 for labor.
- PCM replacement: $500 to $1,500 and $100 to $120 for labor.
Frequently Asked Questions (FAQs)
1. Is It Safe To Drive With P0603 Code?
No, it’s not safe to drive with P0603 Code since it can lead to severe issues like rough acceleration and gear slippage.
This may put your life at risk. It’s better to check the problem, fix it, and then drive.
2. How To Manually Reset PCM?
Press the PCM info button for about 10 seconds to reset the control module. As the display appears, press PCM Car, tap on Option> Set PCM System> Reset PCM> Vehicle Handover> Yes> Yes.
Note that, this works to reboot PCM in Porsche cars. The settings process may vary based on brands and models. So, make sure to check the manual.
3. What Are The Signs Of A Failing PCM?
Symptoms of failing PCM include illuminated check engine light, start problems, engine stalling, misfiring, and unpredictable shifting.
You’ll also get different error codes. One of them is P0603 when KAM malfunctions due to bad control module.
in Conclusion P0603 Code 7.3 Powerstroke
Getting a P0603 in 7.3 Powerstroke isn’t something to worry about if the issue is trivial. Sometimes disconnecting the battery, loose connection, or updating software can send the code. Once you fix the battery or update the program properly, it should help you clear the alert.
However, the same code can indicate serious problems like defects in the internal system. In that case, I suggest you use OBD2 scanner to pinpoint the trouble and fix it. Make sure to change the components that fail.
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Nasruddin is a passionate car enthusiast with a love for troubleshooting and diagnosing all sorts of vehicle problems. With years of experience in OBD diagnostics, Nasruddin, has become an expert in identifying and solving complex automotive issues.
