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CS
POWERTRAIN CONTROL MODULE (Continued)
request, the PCM can determine the volume of fluid
used to apply or release a friction element.
The volume of transmission fluid needed to apply
the friction elements are continuously updated for
adaptive controls. As friction material wears, the vol-
ume of fluid need to apply the element increases.
Certain mechanical problems within the clutch
assemblies (broken return springs, out of position
Clutch
L/R
2/4
OD
UD
SHIFT SCHEDULES
As mentioned earlier, the PCM has programming
that allows it to select a variety of shift schedules.
Shift schedule selection is dependent on the follow-
ing:
• Shift lever position
• Throttle position
Schedule
Extreme Cold
Cold
Warm
Hot
CLUTCH VOLUMES
Shift Sequence
Oil Temperature
2-1 or 3-1 coast
downshift
1-2 shift
2-3 shift
4-3 or 4-2 shift
Oil temperature at start-up below
-16° F
Oil temperature at start-up above
-12° F and below 36° F
Oil temperature at start-up above
36° F and below 80 degree F
Oil temperature at start-up above
80° F
ELECTRONIC CONTROL MODULES 8E - 9
snap rings, excessive clutch pack clearance, improper
assembly, etc.) can cause inadequate or out-of-range
clutch volumes. Also, defective Input/Output Speed
Sensors and wiring can cause these conditions. The
following chart identifies the appropriate clutch vol-
umes and when they are monitored/updated:
When Updated
> 70°
> 110°
• Engine load
• Fluid temperature
• Software level
As driving conditions change, the PCM appropri-
ately adjusts the shift schedule. Refer to the follow-
ing chart to determine the appropriate operation
expected, depending on driving conditions.
Condition
Throttle Angle
< 5°
5 - 54°
> 5°
Expected Operation
Park, Reverse, Neutral and 2nd
gear only (prevents shifting which
may fail a clutch with frequent
shifts)
– Delayed 2-3 upshift
(approximately 22-31 mph)
– Delayed 3-4 upshift (45-53 mph)
– Early 4-3 costdown shift
(approximately 30 mph)
– Early 3-2 coastdown shift
(approximately 17 mph)
– High speed 4-2, 3-2, 2-1 kickdown
shifts are prevented
– No EMCC
– Normal operation (upshift,
kickdowns, and coastdowns)
– No EMCC
– Normal operation (upshift,
kickdowns, and coastdowns)
– Full EMCC, no PEMCC except to
engage FEMCC (except at closed
throttle at speeds above 70-83 mph)
Proper Clutch
Volume
35 to 83
20 to 77
48 to 150
24 to 70
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