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BMW P1290 and 123401: electric wastegate cold start not learned
The engine computer couldn't learn the end positions of the electric wastegate actuator on a cold start. Check the linkage and actuator; on some B-series engines BMW traced it to wiring interference.
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Codes on this page
| Code | Definition | Source |
|---|---|---|
| P1290 | Cold start turbocharger wastegate stop not learned (as reported on N20 cars) | JustAnswer |
| 123401 | Electrical wastegate valve, adaptation: cold start not learned | SI B12 28 16 (PDF) |
| 123411 / 123412 | Electrical wastegate valve, limit position teach-in: end stop (wastegate open) not found | SI B12 28 16 (PDF) |
| 123437 | Electrical wastegate valve: jammed closed | SI B12 28 16 (PDF) |
P-codes are the generic OBD-II codes any reader shows. Six-character and four-character hex codes are BMW's own, read with a BMW-capable scanner; the wording is BMW's, from the source shown.
What it means
Turbo engines with an electric wastegate (N20, N26, B46, B48, B58 and others) teach the actuator's open and closed stops at cold start. If that fails, the DME stores 123401 (often shown as P1290 on generic tools) and may limit power with the emissions light on.
Can I keep driving?
Yes, usually in reduced power. Drivable, but boost may be limited until it's fixed. A rattle from the turbo area suggests worn linkage.
Usual causes on BMWs
| Cause | Cars most affected | What you notice | Evidence |
|---|---|---|---|
| Wiring interference (EMC) | F22, F23, F30–F36, G12 with B46, B48 and B58 built to 7/31/2016 | BMW found the heat management module's actuation disturbing the wastegate controller's 5V supply. Harnesses were changed in production from mid-2016; the bulletin gives the repair. | SI B12 28 16 (PDF) |
| Wastegate linkage binding, worn or out of adjustment | N20, B48 and others | Check the linkage moves freely, then run the wastegate adjustment routine and adjust the rod as the tool directs. | BimmerGuide.de |
| Faulty electric wastegate actuator | N63R (G12, service action), B58D (bulletin) | Reduced power and wastegate codes. | SI B11 04 16 (PDF) SI B11 04 24 (PDF) |
A bulletin isn't a recall and doesn't mean your car has the problem; open it for the exact models and build dates.
What to do
- Ask the shop to check linkage free play and run the wastegate adaptation before replacing the actuator.
- If your car is a 2016-or-earlier B46/B48/B58, ask about BMW's wiring bulletin.
Warnings it can bring up
Related codes
Other BMW bulletins that mention it
- SI B01 07 21 Turbocharger wastegate valve actuator: ltd wty ext to 15 years/150,000 miles G30 · May 2021
- SI B11 14 17 N20 and N26 engines: turbocharger electric wastegate actuator linkage pin corrosion E60, E84, E89, E92, E93 and others · Feb 2018
- SI B12 02 21 Service action: inspection of the electronic wastegate actuator connector G30 · May 2021
- SI B01 02 25 F39 F44 B48E turbocharger wastegate valve controller ext ltd wty (elw) 15/150 F39, F44 · May 2025
- SI B12 01 20 S58T engine: faults for turbocharger electric wastegate stored in the DME G01, G02, F97, F98 · Apr 2020
- SI B11 09 17 Turbo wastegate fault codes G11, G12 · May 2017
- SI B11 03 17 N20 and N26 engine timing chain and oil pump drive chain: limited warranty extension E84, E89, E92, E93, F10 and others · Oct 2021
- SI B11 02 21 Class action settlement: N20/N26 timing/oil pump drive chain diagnosis / repair E84, E89, E92, E93, F10 and others · Sep 2021
19 of the BMW bulletins we hold mention it in their text; these are the closest matches.
Sources
- JustAnswer: P1290 on a 2013 328i (N20), "cold start turbocharger wastegate solenoid stop not learned"
- BimmerGuide.de: checking and adjusting the electric wastegate actuator (German)
- NHTSA: BMW technical service bulletins and recalls by VIN
Bulletins are cited in the tables above. Explanations are ours; where a source is an owner report rather than BMW, it is labelled as one.