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Home >> Pontiac >> 1995 >> Sunfire L4-138 2.3L DOHC VIN D MFI >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Scan Tool Testing and Procedures >> Scan Tool Data Definitions >> Transmission Data

Transmission Data

MAP - Scan tool displays a range of 11-105 kPa, 0.0-5.0 volts
The Manifold Absolute Pressure (MAP) sensor is attached to the intake manifold and measures changes in intake manifold pressure which result from engine speed and load changes. The PCM uses this information to adjust fuel delivery and spark timing according to incoming air density.

BARO - Scan tool displays a range of 11-105 kPa, 0.0-5.0 volts
The MAP sensor is also used to measure barometric pressure during ignition key "ON" cycle and during Wide Open Throttle (WOT), allowing the PCM to make fuel delivery and spark timing adjustments for changing altitudes.

TP (THROTTLE POSITION) SENSOR - Range 0.0-5.0 Volts
Used by the PCM to determine the amount of throttle demanded by the driver. Should read 0.20-0.74 volt at idle to above 4 volts at wide open throttle.

TP ANGLE - Degrees
Computed by the PCM from TP sensor voltage. TP angle should read 0% at idle, 100% at Wide Open Throttle (WOT).

A/C CLUTCH
This parameter indicates the commanded state of the A/C control relay. The clutch should be engaged when "ON" is displayed.

CRUISE ENABLED
This ON/OFF display indicates if the PCM is allowing cruise operation. The PCM has the ability to disable cruise control under certain conditions.

TRANS HOT MODE - Scan tool displays "YES" or "NO"
This parameter monitors transaxle temperature. "NO" indicates the transaxle temperature has not exceeded 266°F (130°C). "YES" indicates the transaxle temperature has exceeded 284°F (140°C) and has not cooled to 239°F (115°C).

ADAPTABLE SHIFT - Scan tool displays "YES" or "NO"
This parameter is the monitor of the upshift adapt. "YES" will indicate that the adapt capability is functional. "NO" will indicate that the adapt is not functional.

CURRENT TAP (TRANSAXLE ADAPTIVE PRESSURE) MEMORY
Scan tool displays a range of -16 to +16 psi. This parameter is the amount of pressure that is added to base line pressure to adjust the holding effort of a clutch or a band, while not engine braking or shifting.

CURRENT TAP (TRANSAXLE ADAPTIVE PRESSURE)
Scan tool displays TP Cells 0 through 16 - This parameter indicates the current throttle position cell used for fluid line pressure modification (adaptation).

LONG SHIFT DELAY - Scan tool displays "YES" or "NO"
This parameter will indicate whether a long shift delay occurred during the last shift. "No" indicates a long shift delay did not occur. "Yes" indicates a long shift delay occurred. A delay shift is determined from the time the PCM commands the shift to the start of the ratio change.

LONG SHIFT TIME - Scan tool displays "YES" or "NO"
This parameter will indicate whether a long shift time occurred during the last shift. "No" indicates a long shift time did not occur. "Yes" indicates a long shift time occurred. Long shift time is calculated from the beginning of the ratio change to the end of the ratio change.

ENGINE RUN TIME - Range 0:00:00-18:12:15 HR/MIN/SEC
A measure of how long the engine has been operating. When the ignition is cycled to "OFF" the value is reset to zero.

HISTORY MALFUNCTIONS - Scan tool will display DTC Number
This parameter will display all DTC(s) that are currently stored in PCM memory.

ACTIVE MALFUNCTIONS - Scan tool will display DTC Number
This parameter will display all active DTC(s).

IGNITION 1 - Range 0.0 to 15.0 Volts
This represents the system voltage measured by the PCM at its ignition feed.

TRANS RANGE - Scan tool displays "ON/OFF", "ON/OFF", "ON/OFF"
These parameters are the three inputs from the transaxle Pressure Switch Assemble (PSA). "OFF" represents a B+ voltage signal, "ON" represents a 0 voltage signal.

TCC (TORQUE CONVERTER CLUTCH) RELEASE PRES. (PRESSURE)
Scan tool displays "ON" or "OFF." This parameter monitors the normally closed TCC Release switch. When TCC Release fluid pressure is present, the switch is "ON", indicating the TCC is released. When fluid pressure is not present, the switch is "OFF", indicating the TCC is applied.


GEAR RATIO - Scan tool will display a range of 0.00 to 4.0 to 1
This parameter is the actual transaxle gear ratio. The ratio is calculated from the input and output speed sensors.

TFT (TRANS FLUID TEMPERATURE) SENSOR
Range -40°C to 151°C, -40°C to 304°F - The PCM converts the resistance of the transaxle fluid temperature sensor to degrees. Trans temp is used to determine "Hot Mode" TCC operation.

ETC (ENGINE COOLANT TEMPERATURE)
Scan tool displays a range of -40°C to 151°C (-40°F to 304°F). This parameter is the input signal of the engine coolant temperature sensor. Engine coolant temperature is high (151°C) when signal voltage is low (0 volt), and engine coolant temperature is low (-40°C) when signal voltage is high (5 volts).

TCC (TORQUE CONVERTER CLUTCH) DUTY CYCLE
Scan tool displays a range of 0% to 100% - This parameter is the commanded percentage of "ON" time of the TCC solenoid. 100% represents an ON" (energized) commanded state. 0% represents a (non-energized) commanded "OFF" state.

TCC (TORQUE CONVERTER CLUTCH) RELEASE SW. (SWITCH)
Scan tool displays "OPEN" or "CLOSED" - This parameter monitors the normally closed TCC Release switch. When TCC Release fluid pressure is present, the switch is "OPEN", indicating the TCC is released. When fluid pressure is not present, the switch is "CLOSED", indicating the TCC is applied.

TCC SLIP SPEED
Scan tool displays a range of -6375 to 6375. Torque Converter Slip Speed. Display shows the amount of slip in RPM between the engine and transaxle input shaft from 0 to 8192.

TCC BRAKE SWITCH - Scan tool displays OPEN/CLOSED
This parameter indicates the state of the TCC brake switch circuit input. OPEN indicates a zero voltage input (brake switch open, brake pedal applied). CLOSED indicates a B+ voltage input (brake switch closed, brake pedal released).

SHIFT SOLENOID 1-2 ("A") - Scan tool displays "ON" or "OFF"
When the automatic transaxle is in first or fourth gear, the scan tool should display "ON". When the transaxle is in second or third gear, the scan tool should display "OFF".

SHIFT SOLENOID 2-3 ("B") - Scan tool displays "ON" or "OFF"
When the automatic transaxle is in first or second gear, the scan tool should display "ON". When the transaxle is in third or fourth gear, the scan tool should display "OFF".

CURRENT GEAR - Scan tool will display 1, 2, 3, or OD
This parameter indicates the current command state of the shift solenoids.

1-2 SHIFT TIME - Scan tool displays a range of 0.00 to 8.00 seconds
This parameter is the actual time of the last 1-2 shift, beginning when the PCM commands the shift until the PCM recognizes a ratio change.

2-3 SHIFT TIME - Scan tool displays a range of 0.00 to 8.00 seconds
This parameter is the actual time of the last 2-3 shift, beginning when the PCM commands the shift until the PCM recognized a ratio change.

1-2 SHIFT ERROR
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the difference between the desired 1-2 shift time and the actual 1-2 shift time. This parameter is not accurate at less than 25% throttle position.

2-3 SHIFT ERROR
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the difference between the desired 2-3 shift time and the actual 2-3 shift time. This parameter is not accurate at less than 25% throttle position.

3-4 SHIFT TIME
Scan tool displays a range of 0.00 to 8.00 seconds - This parameter is the actual time of the last 3-4 shift, beginning when the PCM commands the shift until the PCM recognizes a ratio change.

3-4 SHIFT ERROR
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the difference between the desired 3-4 shift time and the actual 3-4 shift time. This parameter is not accurate at less than 25% throttle position.

LAST SHIFT
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the actual time of the last shift.

LAST SHIFT ERROR
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the difference between the desired last shift time and actual shift time.

SHIFT DELAY
Scan tool displays a range of 0.00 seconds to 8.00 seconds - This parameter is the differential in seconds, for a gear change to take place by comparing the ratios.

UPSHIFT REQUEST - Scan tool will display "YES" or "NO"
This parameter will indicate when the PCM is requesting an upshift. "Yes" indicates an upshift is requested. "No" indicates an upshift is not requested.

UPSHIFT - Scan tool will display "YES" or "NO"
This parameter will indicate whether the PCM is currently commanding an upshift. "Yes" indicates an upshift is commanded. "No" indicates an upshift is not commanded.

DS (DOWN SHIFT) REQUEST
Scan tool will display "YES" or "NO" - This parameter will indicate when the PCM is requesting a down shift. "Yes" indicates a down shift is requested. "No" indicates a down shift is not requested.

DS (DOWN SHIFT) IN PROGRESS
Scan tool will display "YES" or "NO". This parameter will indicate whether the trans axle is currently in a down shift. "Yes" indicates a down shift is in progress. "No" indicates a down shift is not in progress.

LATEST SHIFT
Scan tool will display a range from 0.00 to 8.00 seconds - This parameter is the actual shift time of the last upshift.

VEHICLE SPEED (MPH/Km/h)
Scan tool displays a range of 0.00 to 255 mph - This parameter is the input signal from the vehicle speed sensor.

ENGINE SPEED - Range 0.00 to 9999 rpm
Engine speed is computed by the PCM from the 4X reference input (low resolution circuit). It should remain close to desired idle under various engine loads with engine idling.

PC (PRESSURE CONTROL) ACT (ACTUAL)
Scan tool displays a range of 0.00 amps to 5.00 amps - This parameter is the actual current of the pressure control solenoid circuit at the control module. 0.00 amps (no current flow) indicates actual higher line pressure 5.00 amps (high current flow) indicates actual lower line pressure.

PC (PRESSURE CONTROL) REF. (REFERENCE)
Scan tool displays a range of 0.00 amps to 5.00 amps - This parameter is the commanded current of the pressure control solenoid circuit. 0.00 amps (no current flow) indicates commanded higher line pressure. 5.00 amps (high current flow) indicates commanded lower line pressure.

PC (PRESSURE CONTROL) DUTY CYCLE
Scan tool displays a range of 0% to 100% - This parameter is the commanded state of the pressure control solenoid expressed as a percent of energized of on time. 0% indicates zero "ON" time of the TCC solenoid. 100% represents an "ON" (energized) commanded state. 0% represents a (non-energized) commanded "OFF" state.

TP (POSITION THROTTLE) ANGLE
Scan tool displays a range of 0% to 100% - This parameter is the calculated value from the signal inputs of the APP sensors. 0% throttle indicates closed throttle, 100% throttle angle indicates wide open throttle.

PC (PRESSURE CONTROL) PRESSURE
Scan tool will display a range of 0 to 90 psi - This parameter is the desired torque signal pressure. The pressure is a calculated value based on the PCS commanded reference current.

PC (PRESSURE CONTROL) ENABLE
Scan tool will display "ON" or "OFF" - This parameter indicates the commanded state of the PC solenoid.

KICKDOWN ENABLED
Scan tool displays "NO/YES" - This parameter indicates whether enabling conditions exists for an acceleration mode downshift. "NO" indicates enabling conditions (throttle position, vehicle speed, input speed, etc.) do not exists for an acceleration mode downshift. "YES" indicates enabling conditions exists for an acceleration mode downshift.

POWER ENRICHMENT
Scan tool displays range of "OFF" or "ON" - The scan tool indicates when power enrichment mode is active (moderate to heavy acceleration).

TRANS ISS (INPUT SPEED SENSOR)
Scan tool displays a range of 0.00 to 8192 RPM - This parameter indicates the rotational speed of the transaxle input shaft expressed as revolutions per minute.

TRANS OSS (OUTPUT SPEED SENSOR)
Scan tool displays 0.00 to 8192 RPM - This parameter indicates the rotational speed of the transaxle output expressed as revolutions per minute.

LOOP STATUS
Scan tool will display "Open" or "Closed" - "Closed" indicates the PCM is controlling fuel delivery according to the oxygen sensor voltage. "Open" indicates the PCM ignores the oxygen sensor voltage and bases fuel delivery on TP sensor, ECT sensor and MAP sensor inputs.

PRNDL P, A, B, C
Scan tool displays "HIGH" or "LOW" - A transmission range switch is used as an input to let the PCM know what position the gear select lever is in. Scan tool status will switch from "HIGH" to "LOW" as different combinations are met. In park, PRNDL "P" and "A" will be "LOW"; "B" and "C" will be "HIGH."
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