U059AInvalid Data Received From DC/DC Converter Control Module B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Converter B is a second DC/DC unit, used when one voltage support stage is not enough or when separate networks need their own supply. FCA is the only maker that names it publicly: in powertrain module updates for the 2019 Jeep Cherokee with the 3.2-litre V6 and engine stop-start (18-023-19 and follow-ups such as 18-020-21), the PCM lists both U0599 and U059A for invalid data from DC-to-DC converters A and B, plus U0299 for lost contact with converter 2. The customer complaint in those bulletins is a MIL and an engine that sometimes fails to restart after a stop-start event, and the fix is new PCM software rather than a new converter. A failing second converter mostly shows up as start-stop being withdrawn or electronics resetting during restarts.
- What you may notice
- Check engine light
- Engine does not restart after a stop-start event
- Stop-start function withdrawn
- Likely causes
- LikelyPowertrain controller software evaluating converter B data incorrectly (FCA 18-023-19)
- PossibleSecond DC/DC converter faulty
- RareWiring or ground connection of converter B poor
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.