SW1 L4-1.9L SOHC VIN 8 (1996)
Transmission Temperature Sensor/Switch: All Technical Service Bulletins
TFP, TCC Actuators - Do Not Test Correctly
BULLETIN NO.: 95-T-45
ISSUE DATE: October, 1995
GROUP/SEQ. NO.: Transaxle-06
CORPORATION NO.: 587104
SUBJECT:
During Special Test for Actuators the TFP and TCC Actuators Do Not Test Correctly
(Install New PCM Calibration)
MODELS AFFECTED:
1996 Saturns equipped with MP6 base automatic transaxles built before and including VIN TZ144068.
CONDITION:
When using a portable diagnostic tool (PDT), with data cartridge 204036 installed in PDT, or Scan tool to perform the "Special Test" for "Actuators"
(called the "Transaxle Actuator Quick Check" in the service manual), on a base automatic transaxle, the transaxle fluid pressure (TFP) actuator will pulse
width modulate (PWM) at a lower frequency than intended (8 Hz instead of 32 Hz). Also, the torque converter clutch (TCC) actuator will not pulse
width modulate, but only click once.
IMPORTANT:
The "Transaxle Actuator Quick Check" for 2nd, 3rd, and 4th gear actuators functions normally.
CAUSE:
PCM calibration does not have parameters for the 1996 base automatic transaxle that are necessary for performing the "Transaxle Actuator Quick
Check" for the TFP and TCC actuators.
CORRECTION:
Check for diagnostic trouble codes (DTCs) and perform the following procedure.
PROCEDURE
1.
Connect PDT (with data cartridge 204036 installed in PDT), or Scan tool and record any DTCs that may be stored in PCM memory.
a.
If one or more of the following transaxle fluid pressure and/or TCC actuator DTCs have been set in PCM memory, they must be diagnosed
after the new service calibration has been downloaded into the PCM since the Actuator Quick Check will not operate correctly.
Transaxle fluid pressure and TCC actuator DTCs: P0740, P0741, P0742, P0743, P0744, P0745, P0746, P0747, P0748, and P0749. Make
sure to keep a list of these DTC(s) for diagnosis after the new service calibration has been downloaded into the PCM.
If any one or combination of the above listed DTC(s) have been stored in memory, proceed to step 2 in this bulletin and download the new
service calibration into the PCM.
b.
If any DTCs other than the DTCs listed above are stored in PCM memory, refer to the "1996 Powertrain Controls Service Manual" for
diagnosis. After diagnosing and correcting the condition that caused the DTC(s), proceed to step 2 of this bulletin and download the new
service calibration into the PCM.
IMPORTANT:
If there are DTCs mentioned in both Steps 1a and 1b, diagnose and repair the DTCs that are not transaxle fluid pressure actuator or TCC actuator
related, then proceed to step 2. The DTCs mentioned in step 1a will have to be diagnosed after the new service calibration is downloaded.
