International SA 58 SPN 520210 FMI 3: Blower output circuit over voltage

SA 58 SPN 520210 FMI 3 on International / Navistar trucks means: Blower output circuit over voltage. The failure mode (FMI 3) is “voltage above normal, or shorted to high source”.

Code details

Manufacturer: International (Navistar)
Applies to: International / Navistar body controller (ESC) and multiplexed modules
Fault code: SA 58 SPN 520210 FMI 3
J1939 SPN: 520210
FMI: 3 — Voltage above normal, or shorted to high source
Reporting module: Rear HVAC (source address 58)
Component / signal: HVAC Blower Output
Truck models in source: 3200, 4100, 4300, 4400, 7300, 7400, 7500, 7600, 7700, 8500, 8600, BE 200, CE Bus, CXT, DuraStar, LoneStar, MXT, ProStar, RXT, TranStar, WorkStar

Cause and when it sets

Cause: Voltage above normal, or shorted to high source

What to do next

Read active and inactive codes with the OEM service tool (Diamond Logic Builder can clear previously active codes) and note the occurrence count.
FMI 3 tells the shop the type of failure to test for: voltage above normal, or shorted to high source.
Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.