A 2020 Ford Transit Connect II rolled in with three transmission codes and a technician note that translated to: "The car jerks in gear, barely drivable." The codes present were P2701, P0757, and P0846. When a vehicle behaves this badly, the instinct is often to condemn the entire transmission. However, our diagnostic platform analyzed this specific combination and pointed the technician toward a highly focused testing path.
The primary suspect is hydraulic
The most likely cause, ranked at 55 percent, was a sticking shift solenoid B or an internal valve hang in the valve body. The simultaneous presence of P0757 (Shift Solenoid B Stuck On), P0846 (Pressure Sensor B Circuit Fault), and P2701 (Friction Element B Apply Time) points directly to a mechanical bind in the hydraulic unit.
When solenoid B or its corresponding valve gets stuck in the activated position, the pressure sensor registers an unreasonable oil pressure. Consequently, friction element B does not apply within the expected time window, which is usually 30 to 70 milliseconds. This mismatch creates the harsh jerking and severely reduced drivability the technician reported. The recommended tests here are straightforward: read live data for Solenoid B status versus pressure sensor B, perform a bidirectional click test of the solenoid, and inspect the transmission pan for debris or metal shavings.
Ruling out sensors and wiring
If the solenoid operates correctly, the next possibility at 25 percent is a defective or incorrectly calibrated fluid pressure sensor B. If the sensor has an internal fault or voltage reference issue, the transmission control module (TCM) will think the circuit is pressurized when it is not. This triggers P0846 and cascades into the other two codes. The technician needs to check the sensor's voltage signal with the ignition on and engine off, and inspect the harness pins.
At 15 percent probability, the issue could be damage or corrosion in the transmission wiring harness. The main external connector faces vibration, moisture, and road salt. Oil migration through the connector can also cause voltage drops in the signal wires to both the solenoid and the pressure sensor. A visual check for oil or corrosion and a voltage drop test from the TCM to the connector are required.
The worst case scenario
Ranked lowest at 10 percent is internal mechanical failure of friction element B. Burned clutches, a damaged return spring, or bad piston seals prevent the clutch from building friction within the calibrated time limit. This sets P2701. To confirm this, you have to drop the pan to check the magnets for heavy metal fragments or clutch material, and perform a hydraulic pressure test via an external port.
Moving forward in the bay
When faced with a violently shifting transmission, do not immediately quote a replacement. Start with the bidirectional controls and live data for Solenoid B, then drop the pan. Let me know if you are seeing similar valve body issues on this generation of Transit Connect.