International SA 33 SPN 1043 FMI 1: Bias Voltage reading below normal range

Code details

Manufacturer

International (Navistar)

Applies to

International / Navistar body controller (ESC) and multiplexed modules

Fault code

SA 33 SPN 1043 FMI 1

J1939 SPN

1043

FMI

1 — Data valid but below normal operating range (most severe)

Reporting module

Body Controller (source address 33)

Component / signal

Internal Sensor Voltage Supply

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

Logical signal

Bias_Voltage_Raw_Signal

Cause and when it sets

Cause: Short To Ground in Bias Voltage Circuit

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 1 tells the shop the type of failure to test for: data valid but below normal operating range (most severe).
• Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.

Related fault codes

• International SA 33 SPN 1043 FMI 0 — Bias Voltage reading above normal range
• Cummins Fault Code 283 — Engine Speed/Position Sensor #1 (Crankshaft) Supply Voltage Circuit - shorted high
• Cummins Fault Code 284 — Engine Speed/Position Sensor #1 (Crankshaft) Supply Voltage Circuit - shorted low
• Cummins Fault Code 387 — Accelerator Pedal Position Sensor Supply Voltage Circuit - shorted high
• Cummins Fault Code 443 — Accelerator Pedal Position Sensor Supply Voltage Circuit - shorted low
• Cummins Fault Code 496 — Engine Speed/Position Sensor #2 (Camshaft) Supply Voltage
• PACCAR Fault Code P1644 — PCI ECU 5V Sensor Power Supply Circuit 2 – Voltage Too High or Short Circuit to Supply
• PACCAR Fault Code P1645 — PCI ECU 5V Sensor Power Supply Circuit 2 – Voltage Too Low or Short Circuit to Ground