Allison 1000 & 2000 Gen 4 Fault Codes: P0614 Torque Control Data Mismatch – ECM/TCM

Allison 1000 & 2000 Gen 4 Fault Codes: P0614 Torque Control Data Mismatch – ECM/TCM

CIRCUIT DESCRIPTION:
Shift Energy Management (SEM) allows the Transmission Control Module (TCM) to request torque reduction from the engine controller. By reducing torque, shifts can be made quicker, at a more consistent output torque which reduces clutch temperatures and increases clutch life. When an engine torque rating exceeds 580 lb ft, Lower Range Torque Protection (LRTP) is used. This feature limits engine torque in lower ranges to protect the transmission from damage if a stall condition occurs.

CONDITIONS FOR RUNNING THE DTC:
1. No DTC U2105 CAN bus error.
2. The components are powered and ignition voltage is greater than 9V and less than 18V (12V TCM) or greater than 18V and less than 32V (24V TCM).
3. Engine speed is greater than 200 rpm and less than 7500 rpm for 5 seconds.
4. This test runs for 30 seconds for the first 20 engine starts after the engine is detected on the J1939 CAN.
5. Engine must be identified by the TCM as an approved make and model.
6. Engine’s torque configuration message (peak torque) must be greater than allowed without SEM (above 580 lb ft gross input torque).

NOTE: Unapproved engines or low torque engines will operate without setting a P0614.

CONDITIONS FOR SETTING THE DTC:
P0614 sets when the TCM detects one of the following conditions:
1. TCM detects a valid engine having the proper torque rating but ECM software is not supporting all the messaging necessary for SEM.
2. TCM detects a valid engine having a torque rating exceeding 580 lb ft that does not support Lower Range Torque Protection (LRTP) messaging.

NOTE: Valid engines with a torque rating exceeding 580 lb ft must have software that is compatible with LRTP or a P0614 is set.

ACTION TAKEN WHEN THE DTC SETS:
1. DTC P0614 is stored in the TCM history.
2. The CHECK TRANS light illuminates.
3. If the TCM and engine ECM software are not compatible, the transmission will be restricted to reverse, neutral, first range, or third range.
4. The TCM inhibits TCC engagement.
5. The TCM freezes shift adapts (DNA).

CONDITIONS FOR CLEARING THE DTC/CHECK TRANS LIGHT:
A Scan Tool may be used to clear the code from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
None