Usage:
NOTE: This Program can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS5535" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.
NOTE: This Revised Service Letter replaces the January 31, 1999 Service Letter. Changes have been made to the Action Required.
Termination Date
January 31, 2000Problem
The inching modulation may not work properly on certain 12H, 120H, 135H, 140H, 143H, 160H, and 163H Motor Graders. There may be a jerk when shifting to neutral and/or during a directional shift with the inching modulation pedal depressed on some of these Motor Graders. A new transmission ECM can be installed to improve the operation.
Affected Product
Model & Identification Number
Group 1
12H (4XM1-1030 2WR1-524 4ER1-340 , 4ER342-343, 4ER345, 4ER348-350, 4ER353-355, 4ER359-363, 4ER365, 4ER400-403, 4ER405-407 2GS1-276 , 2GS278-279, 2GS282-284, 2GS300-301, 2GS309 8MN1-459 5ZM1-288 2LR1-272 , 2LR275-294)
120H (4MK1-223 6TM1-345 2AN1-71 5FM1-463 , 5FM465, 5FM467-493, 5FM495-509, 5FM550-573 9YR1-272 , 9YR278-279 3GR1-46 6NM1-239 , 6NM241-254 9FN1-417 )
135H (3YK1-165 8WN1-289 )
140H (2ZK1-1471 8JM1-260 9ZN1-129 5HM1-816 , 5HM818-828, 5HM830-831, 5HM835-840 9TN1-85 , 9TN87, 9TN89, 9TN97, 9TN120-127, 9TN129-151, 9TN153, 9TN156-159 3AS1-399 8KM1-360 , 8KM363-365, 8KM369-393 3FR1-116 )
143H (1AL1-254)
160H (9EJ1-367 9JM1-330 2FM1-349 3GM1-49 2HS1-336 6WM1-330 , 6WM332-340 3HR1-11 )
163H (5AK1-104)
Group 2
12H (2GS1-359 2LR1-294 2WR1-641 4ER1-499 4XM1-1395 5ZM1-288 8MN1-459 )
120H (2AN1-103 3GR1-46 4MK1-403 5FM1-799 6NM1-239 , 6NM241-254 6TM1-365 9FN1-429 , 9FN439-470 9YR1-269 )
135H (3YK1-266 8WN1-289 )
140H (2ZK1-2391 3AS1-399 3FR1-151 5HM1-1149 8JM1-279 8KM1-393 9TN1-299 9ZN1-204 )
143H (1AL1-407)
160H (2HS1-349 2FM1-399 3GM1-79 6WM1-640 9EJ1-509 9JM1-349 )
163H (5AK1-155)
Parts Needed
Group 1
- 1 - 1546527 Control Group
Group 2
- 1 - 1546527 Control Group
Action Required
NOTE: Group 1 machines may experience the inching modulation problem which was previously covered by Service Letter PS5250, dated April 26,1997. This Service Letter replaces PS5250 which has been canceled. The software in the ECM to correct the inching modulation has not changed between the two letters. If PS5250 was applied to any of these machines, this Service Letter does not need to be applied, except if the machine experiences the jerk when a shift to neutral or a directional shift is made.
NOTE: Group 1 and Group 2 machines have the earlier design ECM that is not flashable.
NOTE: Group 2 machines may experience the jerk during shifts.
Group 1 and Group 2
1. Affected Product that required the August 6, 1996 Service Letter - PI1306 - must have that Program completed before there is any attempt to do this Program.
NOTE: This Program must not be implemented on any of the Affected Product where the customer has refused to have the August 6, 1996 Service Letter - PI1306 - completed. This rework is not compatible with Affected Product that required PI1306 but failed to have it completed.
2. Remove the cover off the front lower area of the operator's seat box.
3. Remove the existing transmission electronic control module (ECM).
4. Install the 154-6527 Control Group. Program the new ECM with the correct transmission configuration code. Follow the procedure given in the service manual module "Transmission Electronic Control For Countershaft Transmissions", Form No. SENR6982.
5. Install the cover back on the front lower area of the operator's seat box.
Service Claim Allowances
NOTE: This is a 1-hour job.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.