Transmission · Powertrain · generic (SAE-defined)
P0758: Shift Solenoid "B" Electrical
P0758 means the transmission computer has found an electrical fault, such as an open circuit or a short, in the circuit that controls shift solenoid B.
Standard title per SAE J2012 / ISO 15031-6 · Updated 2026-11-07 · By CarWhere Research
How P0758 sets
The powertrain or transmission control module (PCM/TCM) checks the voltage on the shift solenoid B circuit as it turns the solenoid on and off. When the reading indicates an open, short to ground, or short to power, it stores P0758 and usually locks out normal shifting. Electrical limits and failsafe behavior vary by manufacturer.
Common causes of P0758
Roughly most likely first; the actual cause depends on the vehicle and needs testing to confirm.
- Open or shorted shift solenoid B coil
- Damaged or corroded transmission connector
- Broken or chafed wire in the solenoid B circuit
- Internal transmission harness failure
- Blown fuse or lost solenoid power
- PCM/TCM driver failure
P0758 symptoms
- Check engine light on
- Limp mode with limited gears
- Harsh shifts or engagement
- Slow acceleration
- High engine speed while cruising
How P0758 is diagnosed
- Scan all codes and note whether other solenoid codes share a common power or ground.
- Check fuses and solenoid supply voltage.
- Inspect the external harness and transmission connector.
- Measure solenoid B resistance and compare with specification.
- Test the circuit for continuity and shorts back to the module.
- Confirm repair with a bidirectional solenoid command and road test.
Typical fixes for P0758
- Repair wiring or connector faults
- Replace shift solenoid B or the solenoid pack
- Replace the internal transmission harness
- Restore power supply and replace blown fuse
- Repair or replace the PCM/TCM if confirmed
Replace parts only after testing confirms the cause — a code names the circuit or condition that failed a check, not necessarily the faulty part. We don’t publish per-repair prices; for what households actually spend on upkeep, see car repair costs.
Related codes & warning lights
P0758 FAQ
What does code P0758 mean?
P0758 means the transmission computer has found an electrical fault, such as an open circuit or a short, in the circuit that controls shift solenoid B. The standard definition is "Shift Solenoid "B" Electrical."
Can I drive with a P0758 code?
Only briefly and gently. Most transmissions switch to a failsafe gear when this code sets, limiting acceleration and making highway merging difficult.
What is the most common cause of P0758?
Connector and wiring faults are frequent culprits, along with the solenoid coil itself. A resistance check at the transmission connector quickly shows which side the problem is on.
Does P0758 put the car in limp mode?
Often it does. The module typically stops using the shift solenoids and holds a fixed gear to protect the transmission.
Keep researching
More transmission codes
Sources
- SAE J2012 — Diagnostic Trouble Code Definitions (standard code titles)
- ISO 15031-6 — Road vehicles: communication between vehicle and external equipment for emissions-related diagnostics, Part 6: Diagnostic trouble code definitions
- U.S. EPA — Vehicle Emissions Inspection and Maintenance (I/M) programs
- U.S. EPA, 40 CFR 86.1806-17 — Federal onboard diagnostics requirements for light-duty vehicles
General information written by CarWhere Research, not a diagnosis of your vehicle. Manufacturers can add their own sub-definitions and test conditions; confirm with the factory service information for your year, make and model. Before paying for a repair, check NHTSA for open recalls and your warranty booklet: federal law requires an emissions warranty on major emission-control parts such as the catalytic converter and engine computer.