P2546
Torque Management Request Input Signal A Low
Torque management (powertrain data)
Generic OBD-II
Medium
What it means
P2546 means the "A" torque-management request signal — used by control modules to coordinate engine output with the transmission and other systems — is reading lower than expected. It usually points to a wiring or connection fault on that signal circuit, or a problem in the module sending the request. The vehicle may limit power or alter shifting until the signal is restored.
Medium
Can I keep driving? Often driveable, but power may be limited — modules use torque-request signals to coordinate the engine and transmission, so you may notice reduced power or firmer, odd shifts.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced engine power or limp mode
- Harsh, delayed, or altered shifting
- Traction/stability or cruise features may disable
Common causes
Most likely first
- Low-voltage or open in the torque-request signal circuit between modules (e.g. ECM to TCM)Likely
- Wiring shorted to ground or a poor connection on that circuitCommon
- Corroded connector between the modulesCommon
- A fault in the module that sends the torque requestLess often
How to diagnose & fix
Work through it in order
- Scan all powertrain modules — this code usually appears with companion codes that point to the source.
- Inspect the signal wiring and connectors between modules for opens and shorts.
- Check the grounds and reference voltage on the circuit.
- Repair any damaged wiring or connectors.
- If the wiring is good, diagnose the requesting module, then clear and retest.
FAQ
Quick answers
Is it safe to drive with P2546?+
You can often drive, but the vehicle may hold reduced power or shift oddly for safety. Have it diagnosed before towing or long trips.
Can I just clear P2546?+
It returns while the circuit fault or requesting module is unresolved. Trace the low signal first.
Related codes
Often seen with P2546
Read & clear P2546 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