A/T - Poor Shift Quality: Overview
NO: 18-24-95GROUP: Veh. Performance
DATE: Jun. 23, 1995
SUBJECT:
Improved Transmission Shift Quality
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 18-27-94 REV. A, DATED JAN. 30, 1995 WHICH SHOULD BE NOTED IN THE 1994 TECHNICAL SERVICE BULLETIN MANUAL (PUBLICATION NO. 81-699-95054). THIS REVISION ADDS MODELS AND A PART NUMBER. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS**.
MODELS:
1989 - 1995 (AA) Acclaim/Spirit/LeBaron Sedan
1989 - 1993 (AC) Dynasty/New Yorker/New Yorker Salon
1990 - 1993 (AG) Daytona
1990 - 1995 (AJ) LeBaron Coupe/LeBaron Convertible
**1993** - 1994 (AP) Sundance/Shadow/Shadow Convertible
1990 - 1991 (AQ) Chrysler TC
**1989** - 1995 (AS) Caravan/Voyager/Town & Country
1990 - 1993 (AY) Imperial/New Yorker Fifth Avenue
1993 - 1995 (ES) Chrysler Voyager (European Market)
**1995 (FJ) Sebring/Avenger/Talon**
1995 (JA) Cirrus/Stratus
1993 - 1995 (LH) Concorde/Intrepid/Vision/LHS/New Yorker
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH THE 41TE OR 42LE TRANSAXLE.
SYMPTOM/CONDITION:
1992 AC. & AY VEHICLES BUILT AFTER FEB. 15, 1992 (MDH 02-15-XX). **1995 FJ VEHICLES** AND ALL OTHER 1993-1995 SUBJECT VEHICLES BUILT BEFORE OCT. 24, 1994 (MDH 10-24-XX) ARE VEHICLES EQUIPPED WITH AN ELECTRONICALLY MODULATED CONVERTOR CLUTCH (EMCC).
Vehicles that operate at speeds where EMCC usage is engaged (vehicle speeds between 34 - 41 MPH), may experience early deterioration of the transmission fluid (15,000 - 30,000 miles), exhibit a pronounced shudder during EMCC operation, harsh upshifts/downshifts, and/or harsh torque converter clutch engagements. Performing REPAIR PROCEDURE # 2, which includes updates to the Transmission Control Module (TCM) calibration and eliminates EMCC, will resolve these symptom/conditions. However, if an overheat condition is identified by the PCM or TCM, EMCC operation will be temporarily enabled.
**ALL 1995 FJ VEHICLES** AND ALL OTHER 1989-1995 SUBJECT VEHICLES BUILT BEFORE OCT. 24. 1994 (MDH 10-24-XX).
The TCM calibration used in the 1995 model year 41TE and 42LE TCM is being made available for all vehicles dating back to the 1989 model year. The shift quality improvements and default issues that will be corrected by the new TCM calibration are:
1. COASTDOWN TIP-IN BUMP: Vehicle is decelerated almost to a stop (less than 8 MPH), then the driver tips back into the throttle to accelerate, a noticeable bump may be felt.
2. COASTDOWN SHIFT HARSHNESS: Harsh coastdown shifts on some 4-3, 3-2 and 2-1 downshifts.
3. 1995 LH WITH 42LE TRANSAXLE - SLUGGISHNESS/LACK OF RESPONSE: On some early 1995 LH vehicles built prior to Oct. 24, 1994, a perceived lack of power or transmission responsiveness may be encountered under normal operating conditions. The transmission may not release the converter clutch as desired with increased throttle. This occurs in 4th gear from 35 MPH to 50 MPH.
4. 1989-1994 WITH 41TE & 42LE TRANSAXLES: Harsh shifts and/or vehicle shudder during 3-2 or 2-1 kickdowns at speeds less than 25 MPH.
5. 1993 WITH 41TE TRANSAXLE: Harsh 3-4 upshifts may occur, especially at highway speeds, while using the speed control.
6. 1989-1994 WITH 41TE TRANSAXLE - HARSH/DELAYED GARAGE SHIFTS: Delay is less than 2 seconds and the shift is harsh after the brief delay. NOTE: Delays greater than 2 seconds are caused by transmission hardware malfunction, i.e., valve body, pump, failed lip seals or malfunctioning PRNDL or neutral start switch.
7. 1989-1994 WITH 41TE & 42LE TRANSAXLES- POOR SHIFT QUALITY AFTER A BATTERY DISCONNECT: All transmission learned values are reset to the factory default values if battery power is lost to the TCM. The new 1995 calibration will now retain all learned values in memory after battery disconnect. However. if a transmission is rebuilt or a new transmission or TCM is installed. the Quick Learn procedure must be performed to calibrate Clutch Volume Indexes (CVI) on 1993 and later vehicles (1992 and prior vehicle cannot be Quick Learned).
NOTE:
BEFORE PERFORMING THE QUICK LEARN PROCEDURE, THE TRANSMISSION MUST BE SHIFTED INTO OVERDRIVE (OD) WITH THE ENGINE RUNNING AND THE TRANSMISSION FLUID SET TO THE CORRECT LEVEL. THIS PROCEDURE WILL PURGE THE AIR IN THE CLUTCH CIRCUITS TO PREVENT ERRONEOUS CLUTCH VOLUME VALUES WHICH COULD CAUSE POOR INITIAL SHIFT QUALITY.
8. EARLY 1993 WITH 41TE & 42LE TRANSAXLE - INTERMITTENT SPEED CONTROL DROP OUT: The new service calibration change corrects this condition (this condition was also covered in Technical Service Bulletin 08-09-93 dated Mar. 12, 1993).
9. 1989-1993 WITH 41TE & 42LE TRANSAXLES - New fault code 35 (failure to achieve pump prime) has been added for improved diagnostic capability, and fault codes 21, 22 and 24 are de-sensitized to reduce erroneous limp-in conditions.
Code 21 (OD Pressure Switch Circuit) -
Can be set in error on vehicles with a misadjusted shift cable or if the transaxle is shifted slowly from the OD position to the N position. This typically happens if the operator has a tendency to rest his hand on the shift lever, or overshoots the OD gate while manually shifting from L or 3 to OD. The new software detects this maneuver and shifts the transaxle into Neutral rather than setting code a 21 fault and the subsequent limp-in conditions.
Code 22 and 24 (2-4 and L-R Pressure Switch Circuits) -
In low ambient temperatures (below 32° F or 0° C) some 1989 and 1990 model year vehicles may set this fault in error. Condensation can form and freeze in the PRNDL and/or neutral start switch and cause a delay on garage shifts. The new software prevents this fault code from being set in error and the transaxle going into the limp-in mode.
Code 24 (Low Reverse Pressure Switch Circuit) -
Can get set in error on vehicles where pump prime problems exist. The new fault code 35 (failure to achieve pump prime) has been added and does not trigger a limp-in condition.
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
LABOR OPERATION NO: 21-19-01-91
Module, Transmission Control - Reprogram
(Includes Road Test) 0.7 Hrs.
FAILURE CODE: FM - Flash Module
LABOR OPERATION NO: 21-19-01-90
Module, Transmission Control - Replace
(Includes Road Test) 0.8 Hrs.
FAILURE CODE: P8 - New Part
RELATED OPERATIONS: 21-19-01-50 Fluid Replace Procedure 1.0 Hrs.
21-19-01-51 Pinion Factor 0.2 Hrs.
21-19-01-52 Quick Learn 0.1 Hrs.
21-19-01-53 Cavity 49 Modification 0.1 Hrs.