Calculated engine load
Last reviewed 2026-08-31
Mode 01 · PID 04 (decimal 4)
Description
Normalised engine load as defined by J1979. It is not throttle position and not a direct torque reading.
- PID number
- 04 · 4
- Unit
- %
- Range
- 0 … 100
- Data bytes
- 1
- Formula
- A*100/255
- Also valid as Mode 02 freeze-frame data (same PID number, snapshot at last DTC).
Defined by SAE J1979 / ISO 15031-5. Public index — not a substitute for the paid SAE document.
Signals that use this PID
Sources
Provenance for this page. Official standards outrank community notes. See the confidence policy.
Official standard · high trust
SAE J1979 / ISO 15031-5 Mode 01 PID formulas (public index)
J1979 Mode 01 public formula