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, and C to control shifting.
Also, a grade logic control system has been adopted to control shifting in the D5, D4, and D3 positions. The PCM compares actual driving conditions with programmed driving conditions, based on the input from the throttle position sensor, the engine coolant temperature sensor, the barometric pressure sensor, the brake pedal position switch signal, and the shift lever position signal, to control shifting while the vehicle is ascending or descending a slope.
The PCM turns on the shift solenoid valves A, B, and C to control shifting transmission gear. The combination of driving signals to shift solenoid valves A, B, and C are shown in the table.
| Position | Gear position | Shift solenoid valves | ||
|---|---|---|---|---|
| A | B | C | ||
| D5, D4, D3 | Shifting from the N position | OFF | ON | OFF |
| Stays in 1st | ON | ON | ON | |
| Shifting gears between 1st and 2nd | ON | ON | ON | |
| Stays in 2nd | ON | ON | OFF | |
| Shifting gears between 2nd and 3rd | OFF | ON | OFF | |
| Stays in 3rd | OFF | ON | ON | |
| D5, D4 | Shifting gears between 3rd and 4th | OFF | OFF | ON |
| Stays in 4th | OFF | OFF | OFF | |
| D5 | Shifting gears between 4th and 5th | ON | OFF | OFF |
| Stays in 5th | ON | OFF | ON | |
| 2 | 2nd | ON | ON | OFF |
| 1 | 1st | ON | ON | ON |
| R | Shifting from the P and N position | OFF | ON | ON |
| Stays in reverse | OFF | ON | OFF | |
| Reverse inhibit | ON | ON | ON | |
| P | Park | OFF | ON | OFF |
| N | Neutral | OFF | ON | OFF |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
