SPN 624 — Yellow Warning Lamp
Safe to driveDrivable, but watch it yourself
Updated: 2026-11-14
J1939 code SPN 624. Below — how the fault is worded at the factory by International, KAMAZ, MAZ and YaMZ, and what the second half of the code (FMI) means in the standard.
How to check it yourself
The yellow warning lamp — the fault warning light. The code is about the lamp's own circuit: the unit cannot switch it on. On new vehicles the lamp is on the dash and the command comes over CAN.
Check order
- When the ignition is switched on, does the lamp light for the check?
- Lamp on a wire: the dash connector, the wire, the lamp itself.
- Over CAN — the unit's link to the dash (SPN 639).
- While the lamp does not work, the driver will not know about other faults — read the codes with diagnostics.
Common causes — from most to least frequent
- Link to the dash.
- Lamp wire or connector.
- The dash itself.
International
| FMI 4 | Amber Warning Lamp |
| FMI 5 | Amber Warning Lamp — Amber Warning light malfunction; Amber Warning Lamp |
| FMI 6 | Amber Warning Lamp |
KAMAZ engine (J1939)
| FMI 2 | Warning lamp |
| FMI 3 | Warning lamp |
| FMI 4 | Warning lamp |
| FMI 12 | Warning lamp |
MAZ
| FMI 2 | System diagnostic lamp driver circuit fault - Overheating. Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 3 | System diagnostic lamp driver circuit fault - Short to battery positive. Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 4 | System diagnostic lamp driver circuit fault - Short to ground. Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 12 | System diagnostic lamp driver circuit fault - Open circuit. Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
YaMZ
| FMI 2 | System diagnostic lamp driver circuit fault (Overheating). Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 3 | System diagnostic lamp driver circuit fault (Short to battery positive). Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 4 | System diagnostic lamp driver circuit fault (Short to ground). Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
| FMI 12 | System diagnostic lamp driver circuit fault (Open circuit). Blink code: 3-3-1. Repair: Check the system diagnostic lamp and its wiring. |
What FMI means in J1939
Can I keep driving
Safe to drive. Below — how much time you have and what happens if you keep going.
What happens if you keep driving
This is an electrical fault: an open, a short or a bad contact in the sensor circuit. The value it measures is most likely fine.
You can drive. But until the circuit is repaired this system runs blind and cannot warn you about a real failure.
Nearby: other
- SPN 551Idle Torque, %, Point 1
- SPN 558Accelerator Pedal Idle Limit Switch #1
- SPN 564Inter-Axle Differential Lock Status
- SPN 609Controller #2
- SPN 611System Diagnostic Code #1
- SPN 630Calibration Memory
- SPN 701Auxiliary Input/Output #01
- SPN 705Auxiliary Input/Output #05
- SPN 706Auxiliary Input/Output #06
- SPN 711Auxiliary Input/Output #11
Related codes
- SPN 533Maximum Momentary Override Speed, Point 7
- SPN 527Cruise Control States
- SPN 723Engine speed (auxiliary sensor)
- SPN 746Differential Lock Solenoid Valve #1
- SPN 806ASR Valve, Differential 1
- SPN 920Audible Alarm
- SPN 925Auxiliary Output #2
- SPN 970Engine Auxiliary Shutdown Switch
Makes with this code
KAMAZMAZYaMZInternational
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.