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
Current Gear parameter should correspond with the shift solenoid combination.
Refer to
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
Current Gear parameter should correspond with the shift solenoid combination.
Refer to
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. |
|
3-2 Downshift Solenoid
| --
|
| • | The PCM commands the 3-2 shift solenoid valve ON and OFF. The
scan tool 3-2 Downshift Sol. 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 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: |
| - | The transmission range (PRNDL) must be in Park or Neutral. If
the transmission range is not in Park or Neutral, the message "Engine
running and transmission range is not Park/Neutral" 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. |
|
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. |
|
P1870 Diagnostic Test
| --
| The scan tool guides the technician through a test designed
to help diagnose a DTC P1870 on vehicles equipped with a 4L60-E automatic
transmission. The scan tool gives step by step instructions for performing
the test and displays messages to ensure that the operating conditions are
within test specifications. The scan tool also displays test results and instructs
the technician on further diagnosis.
|
PC Solenoid
| --
|
| • | The PCM commands the amperage (current) to the pressure control
solenoid 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 1500 RPM. If the engine speed is greater than
1500 RPM, the message "TR in park/neutral and engine speed over
1500 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
| --
|
| • | The PCM commands upshifts and downshifts. The scan tool Current
(commanded) Gear parameter should correspond with the shift solenoid combination.
Refer to
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 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 Control Solenoid
| --
|
| • | The PCM commands the duty cycle of the TCC PWM solenoid.
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 control solenoid 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 control solenoid 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. |
|
TCC Enable
| --
|
| • | The PCM commands the TCC enable solenoid valve ON and OFF. The
scan tool TCC Enable 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 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: |
| - | If the transmission range is Park or Neutral, the TCC enable solenoid
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. |
| - | If the transmission range is Park or Neutral and the TCC control
solenoid duty cycle is less than maximum capacity, the TCC enable solenoid
may not be commanded ON. If the solenoid is requested ON during these conditions,
the message "TCC Control Solenoid is not set to maximum Pressure"
appears on the scan tool display. |
| - | If the TCC control solenoid duty cycle is less than maximum capacity,
the TCC enable solenoid may not be commanded ON. If the solenoid is commanded
ON during these conditions the message "TCC Control Solenoid is not
set to maximum Pressure" appears on the scan tool display. |
| - | If the transmission is in hot mode, the TCC enable solenoid 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. |
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