Powertrain Control Module (PCM): Transmission Scan Tool Output Controls
(4T65-E)
Scan Tool Output Control
| Additional
Menu Selection(s)
| Description
|
1-2 Solenoid
| --
|
| • | The PCM commands the 1-2 shift solenoid valve ON and OFF.
The scan tool 1-2 Sol. parameter should match the commanded state.
The scan tool Commanded Gear parameter should correspond with the shift
solenoid combination. Refer to the
Shift Solenoid Valve State and Gear Ratio
table. |
| • | When the ignition is ON, and the engine is OFF, there are no limits
to this control. The solenoid remains ON until commanded OFF, and vice
versa. When the output control is exited, the solenoid state is determined
by the PCM. |
| • | When the engine is running, the following control limits apply: |
| - | Only sequential gear changes are allowed. For example, 1st to
3rd is not allowed. If a non-sequential gear change is attempted,
the message "Non-sequential gear changes not allowed. Gear changes
must be in order" appears on the scan tool display. |
| - | The vehicle speed must be below a calibrated value. If the vehicle
speed is too high, the message "Vehicle speed too high" appears on the
scan tool display. |
| - | The engine speed must be below a calibrated value. If the engine
speed is too high, the message "Engine speed too high" appears on the scan
tool display. |
| - | Downshifts are allowed only when the vehicle speed is below a
calibrated value. If the vehicle speed is too high, the message "Eng. is
on and veh. speed too hi for 3-2 or 2-1 downshift" appears
on the scan tool display. |
| - | The gear requested may not be greater than the current selected
transmission range (PRNDL). For example, 3rd gear is not allowed if the
transmission range is D2. If the gear requested is greater than the
current selected transmission range, the message "Eng. running and gear
request is greater than the current TR" appears on the scan tool display. |
| - | The solenoid remains ON until commanded OFF, and vice versa. When
the output control is exited, the solenoid state is determined by the PCM. |
|
2-3 Solenoid
| --
|
| • | The PCM commands the 2-3 shift solenoid valve ON and OFF.
The scan tool 2-3 Sol. parameter should match the commanded state.
The scan tool Commanded Gear parameter should correspond with the shift
solenoid combination. Refer to the
Shift Solenoid Valve State and Gear Ratio
table. |
| • | When the ignition is ON, and the engine is OFF, there are no limits
to this control. The solenoid will remain ON until commanded OFF, and vice
versa. When the output control is exited, the solenoid state is determined
by the PCM. |
| • | When the engine is running, the following control limits apply: |
| - | Only sequential gear changes are allowed. For example, 1st to
3rd is not allowed. If a non-sequential gear change is attempted, the message
"Non-sequential gear changes not allowed. Gear changes must be
in order" appears on the scan tool display. |
| - | The vehicle speed must be below a calibrated value. If the vehicle
speed is too high, the message "Vehicle speed too high" appears on the
scan tool display. |
| - | The engine speed must be below a calibrated value. If the engine
speed is too high, the message "Engine speed too high" appears on the scan
tool display. |
| - | Downshifts are allowed only when the vehicle speed is below a
calibrated value. If the vehicle speed is too high, the message "Eng. is
on and veh. speed too hi for 3-2 or 2-1 downshift" appears
on the scan tool display. |
| - | The gear requested may not be greater than the current selected
transmission range (PRNDL). For example, 3rd gear is not allowed if the
transmission range is D2. If the gear requested is greater than the
current selected transmission range, the message "Eng. running and gear
request is greater than the current TR" appears on the scan tool display. |
| - | The solenoid remains ON until commanded OFF, and vice versa. When
the output control is exited, the solenoid state is determined by the PCM. |
|
All Wheel Drive Solenoid
| --
|
| • | The PCM commands the duty cycle of the All Wheel Drive solenoid
valve. The duty cycle is represented by a percentage of ON energized time.
Approximately 90-100 percent duty represents an ON energized
commanded state. Zero percent represents an OFF non-energized commanded
state. The scan tool AWD Duty Cycle Parameter should match the commanded
state. |
| • | When the ignition is ON and the engine is OFF there are no limits
to this control. The solenoid remains ON 90-100 percent duty
cycle until commanded OFF zero percent duty cycle, and vice versa.
When the output control is exited, the solenoid duty cycle is determined
by the PCM. |
| • | When the engine is running, the PCM disables this output control. |
|
Clear TAPS (Transmission Adaptive Pressures)
| --
|
| • | The PCM clears, or resets, the TAP cells to the original base
value. |
| • | There are no limits to using this output control. It may be performed
with the engine running or when the ignition is ON, and the engine is OFF. |
|
PC Solenoid
| --
|
| • | The PCM commands the amperage, current, to the pressure control
solenoid valve in order to control transmission line pressure. As the amperage
increases, the line pressure decreases. As the amperage decreases, the
line pressure increases. The amperage range is 0.00-1.10 and may
be commanded in one-tenth amp increments. |
| • | When the ignition is ON, and the engine is OFF, the reference
commanded amperage may be controlled within calibrated limits. The scan
tool parameter "PC Sol. Ref. Current" changes, but the parameter "PC
Sol. Actual Current" does not change. The reference current remains
until commanded otherwise. |
| • | When the engine is running, the following control limits apply: |
| - | When the transmission range is PARK or NEUTRAL, the reference,
commanded, amperage may be controlled within calibrated limits. The engine
speed must be less than 1,500 RPM. If the engine speed is greater
than 1,500 RPM, the message "TR in park/neutral and engine speed
over 1,500 RPM" appears on the scan tool display. Both the scan
tool parameters "PC Sol. Ref. Current" and "PC Sol. Actual Current" change.
Both current readings remain until commanded otherwise. |
| - | When the transmission range is not in PARK or NEUTRAL, the reference
amperage can only be controlled less than the current determined by the
PCM. The PCM does not allow a value to be selected that may cause damage
to the transmission. If the requested amperage is more than allowed
by the PCM, the message "Requested current for the PC Solenoid is too
high" appears on the scan tool display. |
| - | Transmission range DTCs must not be active. If a transmission
range DTC is active, the message "Engine running with transmission DTC
present" appears on the scan tool display. |
|
Shift Transmission
| --
|
| • | When the ignition is ON, and the engine is OFF, there are no limits
to this control. The scan tool shift solenoid states change to match the
Current Gear selected. |
| • | When the engine is running, the following control limits apply: |
| - | The PCM does not allow a shift if it causes the engine RPM to
exceed a calibrated limit. If a gear is requested and the engine speed
is too high, the message "Engine speed too high" appears on the scan
tool display. |
| - | The PCM does not allow a 3-2 or 2-1 downshift if
the vehicle speed exceeds a calibrated limit. If either downshift is requested
and the vehicle speed is too high, the message "Eng. is on and veh.
speed too hi for 3-2 or 2-1 downshift" appears on the
scan tool display. |
| - | The PCM does not allow a 4-3 downshift if the vehicle speed
exceeds a calibrated limit. If a 4-3 downshift is requested and
the vehicle speed is too high, the message "Vehicle speed too high"
appears on the scan tool display. |
| - | The PCM does not allow an upshift if the vehicle speed exceeds
a calibrated limit. If an upshift is requested and the vehicle speed is
too high, the message "Vehicle speed too high" appears on the scan tool
display. |
| - | The PCM does not allow an upshift that is greater than the current
selected transmission range (PRNDL). For example, 3rd gear is not allowed
if the transmission range is D2. If an upshift is requested that is
greater than the current selected transmission range, the message "Eng.
running and gear request is greater than the current TR" appears on
the scan tool display. |
|
TCC PWM Solenoid
| --
|
| • | The PCM commands the duty cycle of the TCC PWM solenoid
valve. The duty cycle is represented by a percentage of ON energized time.
Approximately 90-100 percent duty cycle represents an ON energized
commanded state. Zero percent represents an OFF non-energized commanded
state. The scan tool TCC Duty Cycle parameter should match the commanded
state. |
| • | When the ignition is ON, and the engine is OFF, there are no limits
to this control. The solenoid remains ON, 90-100 percent duty cycle
until commanded OFF, zero percent duty cycle, and vice versa. When the
output control is exited, the solenoid duty cycle is determined by the
PCM. |
| • | When the engine is running, the following control limits apply: |
| - | If the transmission range is PARK, and the transmission is in
hot mode, the TCC PWM solenoid valve may not be commanded OFF. If
the solenoid is requested OFF, the message "TCC OFF command disabled
in Hot Mode" appears on the scan tool display. |
| - | The TCC PWM solenoid valve may not be commanded OFF for
more than a calibrated amount of time. If the solenoid is commanded OFF,
for a certain amount of time, the message "TCC OFF time has been exceeded"
appears on the scan tool display. |
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