Do not driveTo the nearest safe stop
SPN 520212 is a manufacturer number outside the standard J1939 table: different makes can put different things under it. Below — how it is worded by International, KAMAZ, MAZ, SITRAK, Volvo and YaMZ, and what the second half of the code (FMI) means.
InternationalKAMAZMAZSITRAKVolvoYaMZ
| FMI 3 | HVAC Dimmer Output — Dimmer output voltage high |
| FMI 4 | HVAC Dimmer Output — Dimmer output voltage low |
| FMI 3 | CAN: ERC1DR timeout (retarder) |
| FMI 3 | CAN message ERC1DR error - CAN bus message timeout. Blink code: 4-4-2. Repair: Check the CAN line connection to the other CAN devices. |
| FMI 1 | Actual rail pressure below the minimum limit, metering unit control. Scan tool code: P0087. Effect: System shutdown. |
| FMI 3 | LCM output voltage to the instrument panel exceeds 26 V. Wire between the LCM and the instrument panel lamps shorted to the supply wire. |
| FMI 4 | LCM output voltage to the instrument panel is below 2 V. Open wiring between the LCM and the instrument panel, or wire between the LCM and the instrument panel lamps shorted to ground. |
| FMI 3 | ERC1DR CAN message fault (CAN bus message timeout). Blink code: 4-4-2. Repair: Check the CAN line connection to the other CAN devices. |
Do not drive. Stop as soon as it’s safe to do so — don’t keep going.
The code is flagged critical: the manufacturer considers it unsafe to keep driving without checking.
This code alone cannot say what will fail next, so stop at the first safe opportunity and look at it on the spot.
That said, the manufacturer flags this code as critical — if in doubt, it is safer to stop and check on the spot.
Scanner threw several codes at once? Paste the whole list — we will show which one is the root cause and which ones simply followed.