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A/T - Harsh Shift At Low Speed/Speedo. Fluctuates

NO: 08-07-94 Rev. B

GROUP: Electrical

DATE: Dec. 16, 1994

SUBJECT:
Harsh Shifting at Low Speed and/or Digital Speedometer Fluctuates at Idle

THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 08-07-94 REV. A DATED OCT. 21, 1994 WHICH SHOULD BE REMOVED FROM YOUR FILES. THE REVISION CLARIFIES THE SYMPTOMS, CHANGES THE DIAGNOSIS PROCEDURE, ADDS A NOTE TO THE REPAIR PROCEDURE AND PROVIDES A VEHICLE CLEAN POINT. ALL REVISIONS ARE MARKED WITH **ASTERISKS**.

MODELS:

1993 - 1995 (AS) Town & Country/Caravan/Voyager
1993 - 1995 (ES) Chrysler Voyager (European Market)

NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 41TE TRANSMISSION AND A 3.3L OR 3.8L ENGINE **AND BUILT PRIOR TO NOV. 1, 1994, MDH 11-11-XX.**

SYMPTOM/CONDITION:

**The transmission may have inconsistent shift quality at vehicle speeds less than 10 MPH. Harsh 1-2 up shifts or 2-1 coast down shifts can randomly occur, usually 5-10% of the time. As spark plug wires age, harsh shifting may become more frequent. Also, the DIGITAL speedometer may fluctuate slightly (2 MPH) while the vehicle is parked and the engine is at idle**. These symptoms can be the result of induced voltage between the spark plug wires and the output speed sensor wires. No Diagnostic Trouble Codes (DTC's) are set due to the condition.

DIAGNOSIS:

Using the Mopar Diagnostic System (MDS) or the Scan Tool (DRB II/III), verify that all engine and transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order for future reference and repair as necessary before proceeding. If the fluctuating speedometer and/or harsh transmission shift condition is not corrected after repair of any or all DTC'S, continue the diagnosis as follows:

If using the MDS, select EATX State Display/Special Test/RPM Display, then monitor the Output Speed Sensor. With the transmission in **any drive gear and the parking brake and service brakes fully applied (DO NOT ALLOW THE VEHICLE TO MOVE)**, vary the engine speed slowly from idle to 1800 RPM **(DO NOT PERFORM THIS TEST FOR MORE THAN 10 SECONDS AT A TIME)**. If the output speed sensor display does not remain at zero, perform the repair procedure.

If using the DRB II/III, select Transmission Systems/(41TE/State Display DRB II only)/Monitors/RPM Display, then monitor Output RPM. With the transmission in **any drive gear and the parking brake and service brakes fully applied (DO NOT ALLOW THE VEHICLE TO MOVE)**, vary the engine speed slowly from idle to 1800 RPM **(DO NOT PERFORM THIS TEST FOR MORE THAN 10 SECONDS AT A TIME)**. If the output RPM does not remain at zero, perform the repair procedure.

PARTS REQUIRED:

1 6004514 Clip Strap
AR 6015756 Tie Strap
AR 4778138 Black Tape MS-CH71A (3/4 in. x 100 ft. roll)
AR 4688708 Aluminum Tape (1 in. x 60 yd. roll)

REPAIR PROCEDURE:





This procedure involves covering the wiring harness near the spark plug wires with aluminum tape to prevent the spark plug wires from inducing false signals into the output speed sensor wiring that connects to the Transmission Control Module (TCM).

1. Remove and discard the tie strap holding the wiring harness to the right engine mount.

2. Remove the wiring clip from the spark plug cable separator bracket and wiring harness. On some 1993 model vehicles, the wiring may be held to the bracket with a tie strap. If so equipped, remove and discard the tie strap.

3. Remove the wiring clip from the oil dipstick by opening the clip. Do Not remove the clip from the wiring harness or otherwise damage the clip.

4. Wrap the wiring harness (over the convolute) with aluminum tape, P/N 4688708, using a 25% overlap. Wrap the wiring harness from the oil dipstick clip to within 4 in. (100 mm) of the clip at the right engine mount.

**NOTE:
THE TAPES MUST BE APPLIED AS DESCRIBED FOR THE REPAIR TO BE EFFECTIVE.**

5. Cover the aluminum tape **using a 25% overlap** with black tape MS-CH71A, P/N 4778138. **Triple wrap the harness in the area of the A/C compressor high pressure relief valve.**

6. Re-install the wiring harness and clip at the dip stick.

7. Install a tie strap, P/N 6015756, at the right engine mount with the tie strap going through the wiring clip and through the outboard horizontal hole in the engine mount bracket.

8. Install a clip strap, P/N 6004514, to the engine wiring harness at the spark plug cable separator bracket and plug it onto the bracket. If the vehicle originally had the wiring strapped to the spark plug separator bracket, replace the tie strap.

**9. Position the spark plug cables to provide the maximum distance away from the transmission wiring harness.**

10. Repeat the diagnostic procedure to confirm proper Output Speed Sensor/Output RPM values.

NOTE:
IF HARSH SHIFTING CONTINUES TO EXIST, REFER TO TECHNICAL SERVICE BULLETIN **18-27-94 ISSUED IN THE DEC. 30, 1994 COMPAK.**

POLICY:
Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:
Labor Operation No. 08-90-66-98 0.3 Hrs.

FAILURE CODE: XX - Service Adjustment