Chrysler 2005 Crossfire SRT6 Service Manual page 3271

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OPERATION
The transmission control is divided into the electronic and hydraulic transmission control functions. While the elec-
tronic transmission control is responsible for gear selection and for matching the pressures to the torque to be trans-
mitted, the transmission's power supply control occurs via hydraulic elements in the electrohydraulic control module.
The oil supply to the hydraulic elements, such as the hydrodynamic torque converter, the shift elements and the
hydraulic transmission control, is provided by way of an oil pump connected with the torque converter.
The Transmission Control Module (TCM) allows for the precise adaptation of pressures to the corresponding oper-
ating conditions and to the engine output during the gearshift phase, resulting in a noticeable improvement in shift
quality. The engine speed limit can be reached in the individual gears at full throttle and kickdown. The shift range
can be changed in the forward gears while driving, but the TCM employs a downshift safeguard to prevent over-
revving the engine. The system offers the additional advantage of flexible adaptation to different vehicle and engine
variants.
EMERGENCY RUNNING FUNCTION
In order to ensure a safe driving state and to prevent damage to the automatic transmission, the TCM control mod-
ule switches to limp-home mode in the event of critical faults. A DTC assigned to the fault is stored in memory. All
solenoid and regulating valves are thus de-energized.
The net effect is:
• The last engaged gear remains engaged.
• The modulating pressure and shift pressures rise to the maximum levels.
• The torque converter lockup clutch is deactivated.
In order to preserve the operability of the vehicle to some extent, the hydraulic control can be used to engage 2nd
gear or reverse using the following procedure:
• Stop the vehicle.
• Switch off engine.
• Move selector lever to "P".
• Wait at least 10 seconds.
• Start engine.
• Move selector lever to D: 2nd gear.
• Move selector lever to R: Reverse gear.
The limp-home function remains active until the DTC is rectified or the stored DTC is erased with the DRBIII tool.
Sporadic faults can be reset via ignition OFF/ON.
CLUTCH APPLICATION
Refer to the following table for which shift elements are applied in each gear position.
CLUTCH APPLICATION
GEAR RATIO
1 3.59
2 2.19
3 1.41
4 1.00
5 0.83
N X
R 3.16
B1 B2
X* X
X
X
X
X*
* = The shift components required during coast.
AUTOMATIC - NAG1 SERVICE INFORMATION 21 - 201
B3 K1
X
X
X
X
K2 K3
X*
X*
X
X X
X X
X
X
F1 F2
X X
X
X*
X