When repairing your truck, it is essential to take note of the fault codes you encounter and clear them afterward as a preventive measure to ensure your truck’s excellent condition.
That way, you can observe the malfunction patterns that often occur in your truck and see what you can do to avoid them from breaking down.
This article will teach you how to clear Freightliner fault codes using several methods.
Here’s a Short Summary of How to Clear Freightliner Fault Codes:
To clear Freightliner truck fault codes, connect the diagnostic and software tool to the truck’s OBD port and hit the reset function. Some Freightliner fault codes can be cleared by disconnecting, discharging, and reconnecting the truck’s electrical power supply via its battery terminals or fuse.
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What Tools do You Need to Clear Freightliner Fault Codes?
A diagnostic tool is necessary if you want to reset or clear the fault codes on your Freightliner truck.
The OTR Reset Tool and the OBD2 Scanner are the most common diagnostic tools.
The well-known OTR Reset Tool is the most convenient way to clear Freightliner fault codes.
The OTR Reset Tool is a diagnostic tool to check engine lights, reset the after-treatment system, reprogram parameters to default settings, and clear fault codes.
It saves a lot of drivers from regular maintenance and diagnostics since they can immediately find out if there is something wrong with the truck’s engine.
The OBD Scanner is also a reliable tool for troubleshooting fault codes.
Aside from simply scanning the engine fault code, it is also a handy tool for clearing the system codes and restoring them to their default settings.
How Can you Clear Freightliner Fault Codes Without any Tools?
You may find it inconvenient to look for a tool before you can clear the fault codes on your Freightliner.
In that case, you need to learn how to do it without using any tool.
You can remove the batteries from the battery terminal for about 30 seconds to one minute to reset the engine control unit or ECU.
Another method is by turning the ignition on and off. You do not need to remove the batteries while allowing the engine to hard reset.
Aside from this, you can also try pulling off the fuse and putting it back again. It also allows resetting the ECU.
How do you Reset the ECM on a Freightliner?
The engine control module or ECM serves as the brain or the control unit in the truck and other vehicles to function well.
By resetting the ECM, your truck can make certain adjustments or learn about the default or newly-applied settings.
There are different ways to do it:
- Method 1: To reset the ECM on a Freightliner, disconnect the negative battery cable for about 15 to 30 minutes before reconnecting it.
Turn on the truck and drive around to heat the engine. It can immediately learn, store new variables, and clear out old information.
- Method 2: Open the hood and look for the fuse box. Ensure you turn on the ignition before pulling the powertrain control module (PCM).
Wait for three minutes before replacing the fuse and starting the truck. After that, set your vehicle in ideal mode before you drive.
If you notice your truck experiencing a rough idle, wait for five minutes, as it may still adjust to its new settings.
- Method 3: Open the hood and look for the fuse box. Pull the ECM fuse. Wait for 30 minutes before replacing the fuse.
After that, start the truck but let it idle for five minutes before you go driving.
- Method 4: Turn your key to the accessory position. Disconnect the positive battery cable. Wait for 30 minutes.
After that, tap the POS terminal cable to the POS battery three times. Reconnect the terminal cable and start the vehicle. Let it idle for a few minutes before you test drive.
- Method 5: Start your truck and idle until it reaches its normal temperature. Then, turn it off. Go to the fuse box and carefully remove the ECM fuse since the surface is still hot.
After five minutes, reinstall the fuse and turn on your truck, but do not touch the gas pedal. Let it idle first for a few minutes before you can test drive.
How to Reset Freightliner Automatic Transmission
To reset the codes on your Freightliner truck with automatic transmission, you may follow this procedure:
1. Ensure you stop your truck and set it on the parking brake.
2. Turn the selector switch to neutral.
3. Turn off the ignition.
4. Check every harness connector.
5. With the engine shut down, wait a few minutes before restarting the engine.
How to Clear Codes on Freightliner M2?
If you want to clear the codes in your Freightliner M2, you may do so without using any software or diagnostic tool.
First, reboot the ECM by either disconnecting the batteries or the fuses. Wait for about 15 minutes before reconnecting.
If the problem continues even after conducting this procedure, you can contact an authorized Freightliner service facility for a software diagnostic.
How to Reset Check Engine Light on Freightliner M2
To reset the check engine light of Freightliner M2, you should look at the diagnostic display on the dashboard.
Repeat the display and get the codes. If the codes won’t show, it is a possible issue with the ECM power. Thus, it would help if you connected it to the computer.
How to Reset Fault Codes on Freightliner Cascadia
The Cascadia is the most popular model among Freightliner trucks. Thus, many truckers also use this and encounter similar issues.
Since a truck needs regular repairs, you must reset the fault codes after a diagnostic test or maintenance to prolong your truck’s life.
If you do not know how to reset fault codes on Freightliner Cascadia, here’s what you can do:
1. Turn off the battery switch for 15 minutes.
2. While waiting, check the oil level, coolant level, and the check engine lights.
3. After that, turn the knob back to the on position but do not start the truck immediately.
4. Turn the ignition on about half where all the lights on the dashboard appear.
5. Test drive then and see if the fault codes were all cleared.
If the problem persists, contact an authorized Freightliner service facility to assist you further.
How to Reset Check Engine Light on Freightliner Cascadia
When resetting the check engine light of a Freightliner Cascadia, you need to turn its engine first and take the key out.
Look for the kill switch and turn it off. Wait for about 15 to 20 minutes before you turn it back on.
Put the key in and turn it halfway until you hear a beeping sound. Turn the key back off and repeat the same procedure two times more.
After that, look on the dashboard and see if you successfully reset the check engine light.
Again, if the issue continues even after following this procedure, it is always a great solution to contact an authorized service facility to conduct a proper diagnosis.
Freightliner Fault Codes List
Freightliner fault codes help you quickly know the issues on your truck. However, these codes may be challenging to understand, especially for beginners.
At first glance, these fault codes consist of different variables and combinations of letters and numbers, making them look more complex.
These diagnostic troubleshooting codes or DTCs comprise FMI, OC, SPN, and conversion methods.
SPN stands for Suspect Parameter Number. It signifies the fault location number in the particular part or system of the truck.
FMI means Failure Mode Identifier. It shows you the kind of error that appeared, primarily electric-related issues. Several FMIs, from 0 to 31, have corresponding signal issues.
OC is Occurrence Count. As its name implies, it tells you how often a specific error arises.
The difficulty of understanding or reading each code depends on the scanner tool you use. Some may have a format you can easily comprehend than others.
To give you a reference, here’s a list of Freightliner fault codes you can check every time you scan or run a diagnostic on your truck.