Dodge Neon / Neon SRT-4. Manual - part 368

(4) Adjust interlock cable/system as follow-

s:Pry up on cable adjuster lock to release and allow
cable to “self-adjust”. Lock cable adjustment by press-
ing down on the adjuster lock until bottomed at the
cable housing.

(5) Verify correct system operation. Refer to verifi-

cation procedure.

(6) Install shifter bezel (Fig. 300).
(7) Install center console assembly (Fig. 299).
(8) Install gearshift knob and tighten set screw to

2 N·m (15 in. lbs.) torque (Fig. 298).

SOLENOID/PRESSURE
SWITCH ASSY

DESCRIPTION

The Solenoid/Pressure Switch Assembly (Fig. 301)

is external to the transaxle and mounted to the
transaxle case. The assembly consists of four sole-
noids that control hydraulic pressure to the LR/CC,
2/4, OD, and UD friction elements. The reverse
clutch is controlled by line pressure from the manual
valve in the valve body. The solenoids are contained
within the Solenoid/Pressure Switch Assembly, and
can only be serviced by replacing the assembly.

The solenoid assembly also contains pressure

switches that monitor and send hydraulic circuit
information to the PCM/TCM. Likewise, the pressure
switches can only be service by replacing the assem-
bly.

OPERATION

SOLENOIDS

The solenoids receive electrical power from the

Transmission Control Relay through a single wire.
The PCM/TCM energizes or operates the solenoids
individually by grounding the return wire of the sole-
noid needed. When a solenoid is energized, the sole-
noid valve shifts, and a fluid passage is opened or
closed (vented or applied), depending on its default
operating state. The result is an apply or release of a
frictional element.

The 2/4 and UD solenoids are normally applied,

which by design allow fluid to pass through in their
relaxed or “off” state. This allows transaxle limp-in
(P,R,N,2) in the event of an electrical failure.

The continuity of the solenoids and circuits are

periodically tested. Each solenoid is turned on or off
depending on its current state. An inductive spike
should be detected by the PCM/TCM during this test.
It 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 speed ratio or
pressure switch error occurs.

PRESSURE SWITCHES

The PCM/TCM relies on three pressure switches to

monitor fluid pressure in the L/R, 2/4, and OD
hydraulic circuits. The primary purpose of these
switches is to help the PCM/TCM detect when clutch
circuit hydraulic failures occur. The range for the

Fig. 300 Shifter Bezel Removal/Installation

1 - BEZEL
2 - SCREW (4)

Fig. 301 Solenoid/Pressure Switch Assembly

1 - SOLENOID AND PRESSURE SWITCH ASSEMBLY

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PL/SRT-4

SHIFT INTERLOCK SYSTEM (Continued)

pressure switch closing and opening points is 11-23
psi. Typically the switch opening point will be
approximately one psi lower than the closing point.
For example, a switch may close at 18 psi and open
at 17 psi. The switches are continuously monitored
by the PCM/TCM for the correct states (open or
closed) in each gear as shown in the following chart:

PRESSURE SWITCH STATES

GEAR

L/R

2/4

P/N

1st

2nd

OP = OPEN

CL = CLOSED

A Diagnostic Trouble Code (DTC) will set if the

PCM/TCM senses any switch open or closed at the
wrong time in a given gear.

The PCM/TCM also tests the 2/4 and OD pressure

switches when they are normally off (OD and 2/4 are
tested in 1st gear, OD in 2nd gear, and 2/4 in 3rd
gear). The test simply verifies that they are opera-
tional, by looking for a closed state when the corre-
sponding element is applied. Immediately after a
shift into 1st, 2nd, or 3rd gear with the engine speed
above 1000 rpm, the PCM/TCM momentarily turns
on element pressure to the 2/4 and/or OD clutch cir-
cuits to identify that the appropriate switch has
closed. If it doesn’t close, it is tested again. If the
switch fails to close the second time, the appropriate
Diagnostic Trouble Code (DTC) will set.

REMOVAL

NOTE: If solenoid/pressure switch assembly is
being replaced, it is necessary to perform the TCM
Quick Learn Procedure. (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/TRANSMISSION
CONTROL MODULE - STANDARD PROCEDURE)

(1) Disconnect battery negative cable.
(2) Remove air cleaner/throttle body assembly.
(3) Disconnect solenoid/pressure switch assembly

connector.

(4) Disconnect input speed sensor connector.
(5) Remove input speed sensor (Fig. 302).

(6) Remove

three

(3)

solenoid/pressure

switch

assembly-to-transaxle case bolts (Fig. 303).

(7) Remove solenoid/pressure switch assembly and

gasket (Fig. 304). Use care to prevent gasket mate-
rial and foreign objects from become lodged in the
transaxle case ports.

Fig. 302 Input Speed Sensor

1 - INPUT SPEED SENSOR

Fig. 303 Solenoid/Pressure Switch Assembly-to-

Case Bolts

1 - BOLTS
2 - SOLENOID AND PRESSURE SWITCH ASSEMBLY

PL/SRT-4

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21 - 257

SOLENOID/PRESSURE SWITCH ASSY (Continued)

INSTALLATION

(1) Install solenoid/pressure switch assembly and

new gasket to transaxle (Fig. 304).

(2) Install and torque three (3) bolts (Fig. 303) to

13 N·m (110 in. lbs.).

(3) Install input speed sensor (Fig. 302) and torque

to 27 N·m (20 ft. lbs.).

(4) Connect input speed sensor connector.
(5) Install solenoid/pressure switch 8-way connec-

tor and torque to 4 N·m (35 in. lbs.).

(6) Install air cleaner/throttle body assembly.
(7) Connect battery negative cable.
(8) If

solenoid/pressure

switch

assembly

was

replaced, perform TCM Quick Learn procedure.
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL

MODULES/TRANSMISSION

CONTROL

MODULE - STANDARD PROCEDURE)

SPEED SENSOR - INPUT

DESCRIPTION

The Input Speed Sensor is a two-wire magnetic

pickup device that generates AC signals as rotation
occurs. It is threaded into the transaxle case (Fig.
305), sealed with an o-ring (Fig. 306), and is consid-
ered a primary input to the Powertrain/Transmission
Control Module.

Fig. 304 Solenoid/Pressure Switch Assembly and

Gasket

1 - SOLENOID/PRESSURE SWITCH ASSEMBLY
2 - GASKET

Fig. 305 Input Speed Sensor Location

1 - INPUT SPEED SENSOR

Fig. 306 O-Ring Location

1 - INPUT SPEED SENSOR
2 - O-RING

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PL/SRT-4

SOLENOID/PRESSURE SWITCH ASSY (Continued)

OPERATION

The Input Speed Sensor provides information on

how fast the input shaft is rotating. As the teeth of
the input clutch hub pass by the sensor coil (Fig.
307), an AC voltage is generated and sent to the
PCM/TCM. The PCM/TCM interprets this informa-
tion as input shaft rpm.

The PCM/TCM compares the input speed signal

with output speed signal to determine the following:

• Transmission gear ratio

• Speed ratio error detection

• CVI calculation
The PCM/TCM also compares the input speed sig-

nal and the engine speed signal to determine the fol-
lowing:

• Torque converter clutch slippage

• Torque converter element speed ratio

REMOVAL

(1) Disconnect battery negative cable.
(2) Remove air cleaner/throttle body assembly.
(3) Disconnect input speed sensor connector.
(4) Unscrew and remove input speed sensor (Fig.

308).

(5) Inspect speed sensor o-ring (Fig. 309) and

replace if necessary.

INSTALLATION

(1) Verify o-ring is installed into position.
(2) Install and tighten input speed sensor to 27

N·m (20 ft. lbs.).

(3) Connect speed sensor connector.
(4) Install air cleaner/throttle body assembly.

(5) Connect battery negative cable.

SPEED SENSOR - OUTPUT

DESCRIPTION

The Output Speed Sensor is a two-wire magnetic

pickup device that generates an AC signal as rotation
occurs. It is threaded into the transaxle case (Fig.
310), sealed with an o-ring (Fig. 311), and is consid-
ered a primary input to the Powetrain/Transmission
Control Module.

Fig. 307 Sensor Relation to Input Clutch Hub

1 - INPUT SPEED SENSOR
2 - TRANSAXLE CASE
3 - INPUT CLUTCH HUB

Fig. 308 Input (Turbine) Speed Sensor

1 - INPUT SPEED SENSOR

Fig. 309 O-ring Location

1 - INPUT SPEED SENSOR
2 - O-RING

PL/SRT-4

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21 - 259

SPEED SENSOR - INPUT (Continued)

Content .. 366 367 368 369 ..