Chrysler Concorde 2004 Service Manual page 1172

GENERAL INFORMATION
> Solenoid malfunction - LR pressure switch will
not close
> LR Pressure Switch Sense circuit shorted to
battery
Name of code: P0740(38) - Torque Converter
Clutch Control Circuit
When monitored: During Electronically Modu-
lated Converter Clutch (EMCC)
Set condition:
a) The transmission must be in EMCC, with the
input speed greater than 1750 RPM. The TCC/LR
solenoid must achieve it's maximum duty cycle and
still not be able to pull the engine speed within 60
RPM of input speed.
b) If the transmission is in FEMCC and the engine
can slip the TCC by more than 100 RPM (Engine
speed - Input speed) for 10 seconds.
The code will be set if one of these event happens
three times at a throttle angle less than 30 degrees.
Theory of operation: When in 2nd, 3rd, or 4th
gear, the torque converter clutch (TCC) can be
locked when certain conditions are met. The TCC
piston is electronically modulated by increasing
the duty cycle of the LR/TCC solenoid until the
torque converter slip difference (difference be-
tween engine and turbine speed) is within 60 RPM.
Then the LR/TCC solenoid is fully energized
(FEMCC / 100% duty cycle). Torque converter slip
is monitored in FEMCC to ensure adequate clutch
capacity.
Transmission Effects: EMCC will still be avail-
able after code is set. MIL will illuminate after 5
minutes of accumulated slip in FEMCC. The trans-
mission will attempt normal operation (not in
Limp-in) even after the MIL is illuminated.
Possible causes:
> Worn pump bushing and/or failed torque con-
verter - both should be replaced during a rebuild
with code P0740(38) present
> Solenoid pack.
Name of code: P0750(41) - LR Solenoid Circuit
P0755(42) - 2/4 Solenoid Circuit
P0760(43) - OD Solenoid Circuit
P0765(44) - UD Solenoid Circuit
When monitored: Ignition key is turned from off
position to run position and/or ignition key is
turned from crank position to run position, then
every 10 seconds thereafter, or when a gear ratio or
pressure switch error DTC is detected.
Set condition: All four solenoids are tested for
continuity continuously immediately upon start up
and during vehicle operation. For solenoids that
are currently energized, power is momentarily in-
terrupted, then reenergized. For solenoids that are
not currently energized, the solenoid is momen-
tarily energized, then deenergized. Under both
situations, if an inductive spike is not sensed by the
PCM during the continuity check, it is retested
twice. If it fails the test the third time, the appro-
priate code is set.
Theory of operation: Four solenoids are used to
control the friction elements (clutches). The conti-
nuity of the solenoids circuits are periodically
tested. Each solenoid is turned on or off depending
on it's current state. An inductive spike should be
detected by the PCM during this test. If no spike is
detected, the circuit is tested again to verify the
failure. In addition to the periodic testing, the
solenoid circuits are tested if a gear ratio or pres-
sure switch error occurs. In this case, one failure
will result in the appropriate code being set.
Transmission Effects: The MIL will illuminate
and the transmission goes into neutral if code is set
above 35 Km/h (22 MPH), Limp-in mode when
vehicle speed is below 35 Km/h (22 MPH).
Possible causes:
> Open or shorted solenoid circuit(s) between PCM
and solenoid pack.
> Open ground circuit.
> PCM connector problems.
> Solenoid pack connector problem.
> Solenoid Pack.
> PCM
Name of code: P1776(47) - Solenoid Switch Valve
Latched in LR Position
When monitored: Continuously when doing par-
tial or full EMCC (PEMCC or FEMCC)
Set condition: If the transmission senses the LR
pressure switch closing while performing PEMCC
or FEMCC. This code will be set after two unsuc-
cessful attempts to perform PEMCC or FEMCC.
Theory of operation: The solenoid switch valve
(SSV) controls the direction of the transmission
fluid when the LR/TCC solenoid is energized. SSV
will be in the downshifted position in 1st gear, thus
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