Autoshifting Manual Transmission (ASM) Control Circuit
The P0950 code means the vehicle's onboard diagnostic system has detected: Autoshifting Manual Transmission (ASM) Control Circuit. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $200 - $1,200 (parts and labor)
Read and clear transmission codes. Many trans codes are caused by low or burnt fluid -- check level and color before assuming the worst.
Basic scanners only read engine codes. This reads transmission, ABS, and airbag too.
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Common Symptoms
- Check Engine Light illuminated
- Automated shifting not functioning properly
- Harsh or delayed gear changes
- Transmission may default to a single gear
Probable Causes (Ranked by Likelihood)
- Faulty ASM control module Very High
- Wiring fault in ASM control circuit High
- Communication error between ASM module and ECM Moderate
- Software calibration issue in ASM module Low
Frequently Asked Questions
What is an autoshifting manual transmission?
An ASM transmission is essentially a manual gearbox with automated clutch and shift actuators controlled by an electronic module. It provides automatic-like convenience with manual transmission efficiency.
Can a software update fix P0950?
In some cases, a software recalibration or update to the ASM module can resolve control circuit issues. Check with your dealer for applicable updates.
Are ASM transmissions reliable?
ASM transmissions have a mixed reputation for reliability. Regular maintenance of the clutch and actuator systems is essential. Many issues can be prevented with proper servicing.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
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Scan for all DTCs in the ASM module and ECM
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Check communication between the ASM module and other modules
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Inspect ASM control module connector and wiring for damage
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Verify ASM module software version and update if applicable
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Commonly Affected Vehicles
- 2008-2016 Smart ForTwo
- 2010-2018 Fiat 500 (MTA)
- 2010-2016 Opel Corsa (EasyTronic)
- 2012-2018 Peugeot 108 (ETG)
Related Codes
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