Transmission Control Relay; Description; Operation; Transmission Range Sensor - Dodge Dakota Sport 2001 Service Manual

AN
TORQUE CONVERTER (Continued)
(6) Check converter seating with a scale and
straightedge (Fig. 114). Surface of converter lugs
should be at least 13 mm (1/2 in.) to rear of straight-
edge when converter is fully seated.
(7) If necessary, temporarily secure converter with
C-clamp attached to the converter housing.
(8) Install the transmission in the vehicle.
(9) Fill the transmission with the recommended
fluid.
Fig. 114 Checking Torque Converter Seating-Typical
1 - SCALE
2 - STRAIGHTEDGE
TRANSMISSION CONTROL
RELAY

DESCRIPTION

The relay is supplied fused B+ voltage, energized
by the TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal oper-
ating mode.

OPERATION

When the relay is "off", no power is supplied to the
solenoid pack and the transmission is in "limp-in"
mode. After a controller reset, the TCM energizes the
relay. Prior to this, the TCM verifies that the con-
tacts are open by checking for no voltage at the
switched battery terminals. After this is verified, the
voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the TCM mon-
itors the terminals to verify that the voltage is
greater than 3 volts.
AUTOMATIC TRANSMISSION - 45RFE
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is mounted
to the top of the valve body inside the transmission.
The Transmission Range Sensor (TRS) has six
switch contacts that:
• Determine shift lever position
• Supply ground to the Starter Relay in Park and
Neutral only.
• Supply ground to the TCM for backup lamp con-
trol in Reverse only.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transmission
temperature to the TCM and PCM.
OPERATION
The Transmission Range Sensor (TRS) communi-
cates shift lever position to the TCM as a combina-
tion of open and closed switches. Each shift lever
position has an assigned combination of switch states
(open/closed) that the TCM receives from four sense
circuits. The TCM interprets this information and
determines the appropriate transmission gear posi-
tion and shift schedule.
There are many possible combinations of open and
closed switches (codes). Seven of these possible codes
are related to gear position and five are recognized
as "between gear" codes. This results in many codes
which should never occur. These are called
"invalid" codes. An invalid code will result in a DTC,
and the TCM will then determine the shift lever
position based on pressure switch data. This allows
reasonably normal transmission operation with a
TRS failure.
GEAR C5
Park CL
Temp 1 CL
Reverse OP
Temp 2 OP
Neutral 1 OP
Neutral 2 OP
Temp 3 OP
Drive OP
Temp 4 OP
Manual 2 CL
Temp 5 CL
Manual 1 CL
21 - 527
C4 C3 C2
OP OP CL
OP OP CL
OP OP CL
OP CL CL
OP CL CL
CL CL CL
CL CL CL
CL CL OP
CL OP OP
CL OP OP
OP OP OP
OP CL OP
C1
CL
OP
OP
OP
CL
CL
OP
OP
OP
OP
OP
OP