Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Shift Control
The PCM instantly determines which gear should be selected by various signals sent from sensors and switches, and it actuates the shift solenoid valves A, B, C, and D to control gear selection
There are two types of shift solenoid valves
- Shift solenoid valves A and D are normally closed (ON-OPEN/OFF-CLOSE), The normally closed shift solenoid valve port open to allow ATF to pass through when the PCM turns it ON, and the port closes, blocking fluid flow when turned OFF
- Shift solenoid valves B and C are normally open (ON-CLOSE/OFF-OPEN), The normally closed shift solenoid valve port closes, blocking ATF from passing through when the PCM turns it ON, and the port opens, allowing fluid flow when turned OFF
The combination of driving signals to shift solenoid valves A, B, C, and D for each gear are in the following table
| Position | Gear Position | Shift Solenoid Valves | |||
|---|---|---|---|---|---|
| A | B | C | D | ||
| D and S | Shifting from N | OFF | ON | OFF | OFF |
| Stays in 1st | OFF | ON | ON | OFF | |
| Shifting gears between 1st and 2nd | ON | ON | ON | OFF or ON | |
| Stays in 2nd | ON | ON | OFF | OFF or ON | |
| Shifting gears between 2nd and 3rd | ON | ON | ON | OFF or ON | |
| Stays in 3rd | ON | OFF | ON | OFF or ON | |
| Shifting gears between 3rd and 4th | ON | OFF | OFF | OFF or ON | |
| Stays in 4th | OFF | OFF | OFF | OFF or ON | |
| D | Shifting gears between 4th and 5th | OFF | OFF | ON | OFF or ON |
| Stays in 5th | OFF | ON | ON | OFF or ON | |
| N | Neutral | OFF | ON | OFF | OFF |
| R | Shifting from P and N | OFF | ON | OFF | ON |
| Stays in reverse | ON | ON | OFF | ON | |
| Reverse inhibit control | OFF | ON | OFF | OFF | |
| P | Park | OFF | ON | OFF | ON |
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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