SPN 118 FMI 1: brake secondary pressure, below normal, most severe
Secondary brake air pressure is way too low. Type another SPN and FMI to check it.
Secondary brake air pressure is way too low.
- Stop safely and let the air build.
- Listen for leaks.
Paste the whole line if you like: "SPN 3251 FMI 0", "3251/0" or Deere's "003251.00". Plain-words guidance; the service manual wins.
What SPN 118 FMI 1 means
Secondary brake air pressure is way too low.
FMI 1: below normal, most severe
Reading is way too low. Treat it as real until you prove the sensor wrong. (SAE J1939-73: Data valid but below normal operational range, most severe level.)
How urgent it is
Stop the machine. This one can wreck the engine or hurt someone. Shut down where it's safe.
What to check first
- Stop safely and let the air build.
- Listen for leaks.
Plain-words guidance for a foreman, not a repair procedure. Makers add their own codes and steps; the machine's service manual wins.
Next time, Dozer catches the code when it fires.
Plug a CAN logger into the machine's J1939 port, or connect the telematics you have. When a code fires, Dozer opens a repair ticket with the meaning, how urgent it is and what to check.
- The code, the machine and its hours on one ticket
- Severity sorted: keep working, plan a stop, or stop now
- The mechanic gets the checklist before they drive out
- Repeat codes on the same machine get flagged
LIVE EX-04 · SPN 3251 FMI 0 · plan a stop today Photo is an AI-generated stand-in, not a customer site.
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Questions crews ask
What does SPN 118 FMI 1 mean?
Secondary brake air pressure is way too low. FMI 1 means: Reading is way too low. Treat it as real until you prove the sensor wrong.
Can I keep running with SPN 118 FMI 1?
Stop the machine. Shut it down where it's safe and find the cause before you run it again. If the machine derates or the stop lamp is on, stop.
What should I check first for SPN 118 FMI 1?
Stop safely and let the air build. Listen for leaks.
How do I clear SPN 118 FMI 1?
Fix the cause first. Most codes go inactive by themselves once the condition is gone and the engine has run a key cycle or two. Clearing it with a service tool without a fix only hides it until it comes back.
Which machines show SPN 118 FMI 1?
Any diesel that speaks SAE J1939: excavators, dozers, loaders, haul trucks, generators and on-road trucks with Cat, Cummins, Deere, Komatsu, Volvo, Kubota, Perkins and other engines. The SPN means the same thing on all of them; the fix steps can differ, so check the service manual.
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