Chevrolet Equinox Service Manual: Shift Speed Automatic Transmission Unit

1–2 @ 12.5

16

9.9

345

2–3 @ 12.5

26

16.2

561

3–4 @ 12.5

39.5

24.5

852

4–5 @ 12.5

54

33.6

1164

5–6 @ 12.5

71

44.1

1531

6–5 @ 12.5

68.5

42.6

1477

5–4 @ 12.5

51

31.7

1100

4–3 @ 12.5

36

22.4

776

3–2 @ 12.5

23

14.3

496

2–1 @ 12.5

11

6.8

237

1–2 @ 25

21.5

13.4

464

2–3 @ 25

36

22.4

776

3–4 @ 25

48

29.8

1035

4–5 @ 25

64

39.8

1380

5–6 @ 25

115

71.5

2479

6–5 @ 25

68.5

42.6

1477

5–4 @ 25

51

31.7

1100

4–3 @ 25

36

22.4

776

3–2 @ 25

23

14.3

496

2–1 @ 25

11

6.8

237

Calc. Throttle Position

Calc. Throttle Position-(TP) is one of the mostimportant inputs in the transmission shift pattern logic. A verylow TP angle will impact the shift pattern by causing upshifts. Avery high TP angle will impact the shift pattern by causingdownshifts.

Commanded Gear

Based on numerous inputs, the transmission control module(TCM) selects the optimum gear. Once the TCM commands a gear, thepressure control solenoids are activated to hydraulically controlengagement of the proper clutch.

Cruise

When cruise control is activated, the shift pattern isaltered to reduce excessive shifting.

ECT

Shift speed points may be offset to enhance engine coolanttemperature-(ECT) warm-up. Also, operating the vehicleat higher engine speeds will reduce the time to warm the ECT andthe TFT.

Engine Speed

To protect against an over speed condition, engine speed ismonitored. If the engine speed becomes too high, an upshift willoccur.

Engine Torque

Engine torque is used to predict vehicle operatingconditions, in order to determine the optimum gear and provide fora smoother ride.

IMS

The internal mode switch-(IMS) indicates theposition of the transmission manual valve. The operator controlsthis valve by moving the gear range selector. Therefore, thepossible gears may be limited by this valve position.

TCC-PC Sol. Duty Cycle

The torque converter clutch-(TCC) pressurecontrol-(PC) solenoid duty cycle indicates when the TCChas been engaged.

TCC Slip Speed

The TCC Slip Speed indicates the difference between enginespeed and transmission input speed. The TCC is locked when slipspeed is at or near zero, and may be controlling slip when at lowerslip speeds.

TFP Switch 1, 3, 4 or 5

The transmission fluid pressure-(TFP) switch isused to indicate if fluid pressure to a specific clutch has beenapplied or released.

Trans. Fluid Temp.

A lower TFT will extend shift speeds, a higher TFT, or hotmode condition, will invoke shorter shift speeds in order toestablish a shift pattern required to cool the TFT.

Transmission Hot Mode

If the TFT becomes too hot, a hot mode shift pattern is used.The hot mode shift pattern will invoke lower shift speed points toestablish a shift pattern necessary to cool the TFT.

Transmission OSS

The transmission output speed sensor-(OSS) is oneof the most important inputs into the transmission shift patternlogic. A very low transmission output speed will impact the shiftpattern by causing downshifts. A very high transmission outputspeed will impact the shift pattern by causing upshifts.