OBD-II code P1911 indicates that the powertrain control module (PCM) has detected a low voltage condition in the circuit for transmission pressure control solenoid B. This solenoid regulates hydraulic pressure for shift feel and timing; a low output signal can lead to improper transmission operation.
The solenoid itself may have an internal short or mechanical failure, causing low resistance or improper operation.
Wiring between the PCM and solenoid can chafe, break, or short to ground, pulling the signal voltage low.
Corrosion, bent pins, or a loose connector at the transmission bulkhead or solenoid can cause high resistance or intermittent signal loss.
Insufficient fluid level or degraded fluid can affect hydraulic pressure and solenoid performance, triggering the code.
A failing TCM (if separate) or PCM can incorrectly read the circuit or fail to command the solenoid properly, though this is rare.
It means the PCM has detected a low voltage condition in the circuit for transmission pressure control solenoid B, which can affect shift quality.
Driving with this code is not recommended, as it may cause transmission damage, harsh shifting, or sudden limp mode, which can be unsafe.
No, PCM failure is very rare for this code. The most common causes are a faulty solenoid, wiring issues, or low fluid. The PCM should only be suspected after all other possibilities are ruled out.
Repairs often involve replacing the pressure control solenoid, repairing damaged wiring or connectors, or performing a transmission fluid service. PCM replacement is seldom required.