P071A
Transmission Mode Switch A Circuit
Transmission
Generic OBD-II
High
What it means
P071A means the computer has detected a fault in the transmission mode switch circuit — the switch that selects modes such as normal, sport, tow, or economy. The car keeps driving in its default mode; the practical effect is that you may not be able to change shift modes until the switch or its wiring is repaired.
High
Can I keep driving? Yes — the car drives normally; you may just lose the ability to change transmission modes until it is fixed.
Common symptoms
What you'll notice
- Check-engine light on
- Transmission mode button/switch (e.g. sport, tow, economy) not responding
- Transmission stuck in its default shift mode
- Mode indicator light not changing
Common causes
Most likely first
- Faulty transmission mode switchLikely
- Wiring or connector fault in the mode-switch circuitCommon
- Poor connection at the TCM/PCMCommon
How to diagnose & fix
Work through it in order
- Scan and watch the mode-switch input while operating the switch.
- Test the switch for correct open/closed states in each position.
- Inspect the switch wiring and connector for damage and corrosion.
- Replace the mode switch if it does not change state correctly.
- If the switch and wiring are good, check the TCM/PCM connections.
FAQ
Quick answers
Is it safe to drive with P071A?+
Yes. The transmission still shifts in its normal mode; you just may not be able to select sport, tow, or economy modes until it is repaired.
Can I just clear P071A?+
You can, but if the switch or wiring is faulty the code returns and mode selection still will not work; fix the circuit.
Related codes
Often seen with P071A
Read & clear P071A yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX