P0789 — Shift/Timing Solenoid Malfunction (3-2 Shift Solenoid Circuit Electrical)
Drivable short-term, but fix now to avoid damage.
What P0789 means
This code indicates an electrical fault in the shift/timing solenoid circuit, often the 3-2 shift solenoid. It's commonly caused by a failed solenoid, damaged wiring or connectors, or low and dirty transmission fluid, and occasionally a faulty control module. Repairs usually involve testing the circuit and replacing the solenoid or repairing wiring, sometimes along with a fluid service.
Common symptoms
- Check engine light is on
- Erratic, harsh, or delayed shifting
- Transmission slipping between gears
- Vehicle enters limp mode or stuck in one gear
- Reduced fuel economy or sluggish performance
Common causes
- Failed shift/timing solenoid (3-2 solenoid)
- Damaged wiring, connectors, or short in the circuit
- Low, dirty, or contaminated transmission fluid
- Corroded or loose electrical connections
- Faulty transmission control module
Typical repair cost
$150 – $1200
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0789 code?
For short trips, usually yes, but it's risky to keep doing so. A faulty solenoid circuit can cause unpredictable shifting and limp mode, so get it checked soon and drive gently until it's repaired.
How much does it cost to fix a P0789 code?
Often it's on the lower end, since replacing a shift solenoid or repairing wiring may run a few hundred dollars. Costs can climb if the fault is internal or requires significant labor to access the solenoid.
Is a P0789 code serious?
It can be. An electrical solenoid fault can cause erratic shifting and put the transmission into limp mode, so it should be diagnosed and repaired without long delays.
Is P0789 an electrical or mechanical problem?
P0789 is specifically an electrical circuit fault in the shift/timing solenoid, often the 3-2 solenoid. That usually means the solenoid, its wiring, or connectors, rather than worn internal gears.