What Is Fault Code SPN 5435 FMI 7 and FMI 11? (Freightliner)
When you look up codes do not ignore the GHG 14, GHG 17, or the EPA 10. The numbers refer to the regulation years your repairs have to meet once the repairs are completed.
The SPN 5435 FMI 7 code means- Non-Def Flow Situation: Aftertreatment 1 Diesel Exhaust Fluid Pump State Mechanical System Not Responding Or Out Of Adjustment; Pump Blockade. This should be a mechanical repair.
To learn more about these codes, just continue to read our article. It explores both of them so you have the best information available to make your repair. Take a few minutes to see what this information can do for you and how it can help make your repair go smoother.
Freightliner SPN 5435 FMI 7
What the code says for Freightliner is that the Non-Diesel Exhaust Fluid (DEF) Flow Situation has a speed problem. The flow is low according to the data sheet on this particular fault code.
When you see this code, you should also see the MIL and CEL lights illuminated. Plus, you should experience a 25% derate soon after the code is set. A further explanation is that the pump is working, it just cannot operate at full speed.
The good news is that there are not that many steps to be taken to resolve this issue. When you see this code, and it is something you should get in the habit of doing, make a log entry just in case you have to talk to customer service.
The log entry will help you explain what you see to the technician so they can help you better. The possible sources for this code are:
- debris in the line
-low DEF fluid, frozen DEF fluid
-the pump is starting to fail.
You are looking mainly for any blockage in the line that would interrupt the flow of DEF fluid.
The Steps To Repair SPN 5435 FMI 7
The best part of many of these fault codes is that they do not take a lot of effort to repair them. This fault code only has six steps to follow and the data sheet has a diagram in a table to help you. Here are those 6 steps:
1. Connect DDDL/DDRS 7.08 SP2 or newer.
a. If SPN 4374/FMI 3, 4, or 5 are active, repair those faults first.
b. If not, Go to step 2.
2. Turn the ignition OFF (key OFF, engine OFF).
3. Inspect the DEF pump harness wiring and connector for damage, wire chafing, bent, spread, or loose/corroded pins.
a. If damage is found, repair as necessary. Go to step 5.
b. If no damage is found, Go to step 4.
4. Disconnect the DEF pressure line at the DEF pump. Refer to the section "Removal of the GHG14 Diesel Exhaust Fluid Lines" Run a hose from the DEF pump outlet into a DEF-safe container.
5. Turn the ignition ON (key ON, engine OFF).
6. Run Selective Catalytic Reduction Airless Dosing System – (SCR ADS) Self-Check routine. Monitor DEF flow into the container.
a. If DEF flow is noted or the DEF pump rpm signal is above 600, reconnect the pressure line to the DEF pump. Verify repairs by running DEF ADS Self-Check. If ADS Self-Check is successful, clear codes and release the vehicle.
b. If no DEF flow or rpm signal below 600 is noted, replace the DEF pump. Refer to the section "Removal of the GHG14 Diesel Exhaust Fluid Pump Module"Verify repairs by running DEF ADS Self-Check.
There are alternative instructions to help solve this problem:
“After you turn the truck off, the pump will automatically do a reverse purge of the lines to clear out the line to prevent the lines from freezing. When that happens, if there is debris, the lines will flush.
If the code comes back, then I would suggest starting with the DEF filter then if that doesn't resolve, the lines will need to get flushed and possibly the pump may need to be replaced.”
It is possible to drive with the amber light illuminated. The mechanic dispensing this advice says you can drive about 500 miles as long as the code does not become active.
Just keep an eye on it as you may see the 25% derate function enacted and that may slow you down some.
SPN 5435 FMI 11
This is what the official SPN fault code list has to say about this error code- Voltage Above Normal, Or Shorted To High Source; Pump Block Loop Error Detection.
Unfortunately, there are no data sheets or other websites talking about how to fix this code. The reason may be that FMI 11 only says - Failure mode not identifiable.
This may mean that you or your vehicle’s electrician will have a tough time investigating this problem and finding the source. You may have to go through many different components with your multi-meter and see where the problem is.
Not every fault code is going to be helpful or save you time. You may have to go to a qualified mechanic to get to the bottom of this code. The mechanic should have dealer-level equipment to help diagnose the problem more thoroughly and accurately.
This may not be a DIY fix at any time due to the unidentifiable nature of this code.
Some Final Words
Fault codes can get frustrating. While designed to be helpful, and most are, some codes only complicate the situation like the FMI 11 option does above. When it comes to the FMI 7 code, do the easier repair option first.
That should save you time if there is an obstruction. If the code clears when you are done, that is great. You are on the road again. If the FMI 7 code turns off but the yellow light remains, just keep an eye on the dash.
It may become active again as you make your way home or to the closest repair shop when you are far from home.
