What Is Fault Code SPN 1590 FMI 19? (Freightliner)

When you get an error code on your dash, you expect to be able to find the right instructions to perform the repair. That is not always going to happen and it is disappointing when you get a code that has a data sheet explaining the fault but has no repair instructions.

The fault code SPN 1590 FMI 19 points to this problem- Adaptive Cruise Control - General Error. The data sheet does not provide any repair information and simply states ‘there is no repair for this issue at this time.’

To learn more about this fault code and some possible solutions, just continue to read our article. It comes with the information you want to know about including possible repair ideas suggested by mechanics. The picture is grim though.

Freightliner SPN 1590 FMI 19


When you receive this code, you need to make sure you have the following feature- ProStar Models Equipped with Wingman Feature Codes 8TKW or 8TPL. That is what this code is for.

The description of this code is- “When battery voltage level reaches the low voltage threshold, the Body Controller engages the load shed relay. This removes the power supply from components to prevent the batteries from becoming completely discharged.

The forward-facing radar in the Collision Avoidance System is an item that is powered down during load shed. This causes SPN 1590 FMI 19 Adaptive Cruise Control not detected on J1939 to become active.”

That may not be very helpful except that you should check your batteries to see if they need to be recharged or replaced so that there is full power to this system.

That is the advice of one mechanic we came across dealing with this fault code. However, the data sheet for this fault simply states- “The fault should go inactive when the engine is started and the unit is no longer in load shed. There is no repair for this issue at this time.”

Those are not words anyone wants to hear or read. There is a glimmer of hope though as another mechanic has stated- “This fault code may be set if the driver does not wait for gauge sweep after turning the ignition on.

This fault code may be set if the driver does not wait for a gauge sweep after turning the ignition on. It basically throws off the software indicating the self-check was not allowed to complete before starting the engine. Clear the faults and cycle the key switch. Wait for the gauges to cycle the self-test then start. Let me know”.

Do what the second mechanic said and see if that solves your problem. You can read the data sheet here and the second mechanic here.

SPN 1590 FMI 19 International


The news for this specific brand of vehicle is bleak as well. The mechanic does say something different than the above two reports and it may be a bit more helpful to you. Here is what he said:

This fault code is for the adaptive cruise control. This means that the front radar can not communicate over the 1939 data link. The first thing would be to check the connections on the radar.

Then follow the harness thru the bumper and near the cooling pack for any issues. If none are found then check for power and ground at the connector end. Then perform the data link check. If all of that is fine then the radar will need to be replaced. “ (source)

The vehicle in question was the maxxforce prostar 2012 international. If your vehicle does not have the ProStar Models Equipped with Wingman Feature Codes 8TKW or 8TPL then you may not see this code at any time.

SPN 1590 FMI 9


When you see these numbers and letters pop up on your screen, they are telling you that- Adaptive Cruise Control Message Not Received. The good news for this and the previous code is that you should not see any lamps illuminated and your engine performance should not be affected.

Part of the repair is to attach the DiagmosticLink to your vehicle and verify that your vehicle has the adaptive cruise control system. If it doesn’t then you just make sure the PGR043 is disabled. Then verify the repair.

If your vehicle does have the adaptive cruise control feature then step 5 is what you want to follow. That step says:

Verify that the "adaptive cruise control enable" parameter PGR043 is enabled; refer to the Application and Installation (A&I) manual. Is parameter PGR043 enabled with the correct Adaptive Cruise Control System?

a. Yes; refer to OEM literature to diagnose the concern. Verify repair.

b. No; change parameter PGR043 to enabled. Verify repair.”

That is all there is to it. This repair is for this code- SPN 1590/FMI 9 - EPA07 - EPA10. There is a difference between this code and the following- SPN 1590/FMI 9 - GHG14

Step 4 for that latter code is for when you do not have the ACC and it reads- “is parameter PGR043 disabled” If it is, you should verify the repair. If it isn’t, then change it to disabled.

Step 5 is for when you do have ACC and it reads- “For vehicles equipped with Detroit Assurance, parameter PGR043 should be set to 0 (zero) disable. Is parameter PGR043 set to disable?

a. Yes; replace the CPC. Verify repair.

b. No; change parameter PGR043 to disable. Verify repair.” (source)

Some Final Words

When you read your SPN FMI codes, look for the letters EPA & GHG. If they are following the MI code, do not assume the same repair instructions are for both sets of letters.

Make sure to read all repair instructions so you know what to do. As you can see, there are slight differences in the instructions. Do not take 'no'.

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