Safe to driveUntil the next service
SPN 523550 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by KAMAZ, MAZ and YaMZ, and what the second half of the code (FMI) means.
| FMI 2 | Time processor unit (TPU) deviation from CPU timer |
| FMI 2 | Real-time clock processor error - Controller system time error. Blink code: 1-1-5. Repair: Replace the ECU. |
| FMI 2 | Electronic time processor fault (Controller system time error). Blink code: 1-1-5. Repair: Replace the ECU. |
| SPN 523550 FMI 2523550/2 · 523550.2 | data erratic or intermittent |
Safe to drive. Below — how much time you have and what happens if you keep going.
A standalone fault with no immediate consequences for driving.
Show the codes at the next service. If a second code from the same system appears, stop putting it off.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.