2002 DODGE RAM relay

REMOVAL
The relays are located in engine compartment,
bolted to left inner fender below left battery (Fig. 30).
The mounting bracket and both relays are replaced
as an assembly.
(1) Disconnect both negative battery cables at both
batteries.
(2) Disconnect four relay trigger wires at both
relays (Fig. 30). Note position of wiring before remov-
ing.
(3) Lift four rubber shields from all 4 cables (Fig.
30).
(4) Remove four nuts at cable connectors (Fig. 30).
Note position of wiring before removing.
(5) Remove three relay mounting bracket bolts
(Fig. 30) and remove relay assembly.
INSTALLATION
The relays are located in engine compartment,
bolted to left inner fender below left battery (Fig. 30).
(1) Install relay assembly to inner fender. Tighten
mounting bolts to 4.5 N´m (40 in. lbs.) torque.
(2) Connect eight electrical connectors to relays.
(3) Connect battery cables to both batteries.
INTAKE AIR TEMPERATURE
SENSOR
DESCRIPTION - DIESEL
The intake manifold air temperature sensor is
installed into the rear of the intake manifold (Fig.
31) with the sensor element extending into the air
stream.
OPERATION - DIESEL
The IAT provides an input voltage to the Engine
Control Module (ECM) indicating intake manifold air
temperature. The input is used along with inputs
from other sensors for intake air heater element
operation, for engine protection, fuel timing and fuel
control. As the temperature of the air-fuel stream in
the manifold varies, the sensor resistance changes.
This results in a different input voltage to the ECM.
Fig. 29 Intake Manifold Air Heater Relays Location
1 - BATTERY (LEFT SIDE)
2 - RELAY MOUNTING BOLTS (3)
3 - RELAY TRIGGER WIRES (4)
4 - INTAKE AIR HEATER RELAYS (2)
5 - RUBBER SHIELDS (4)
6 - CABLES TO BATTERY (+)
Fig. 30 Intake Manifold Air Heater Relays
1 - BATTERY (LEFT SIDE)
2 - RELAY MOUNTING BOLTS (3)
3 - RELAY TRIGGER WIRES (4)
4 - INTAKE AIR HEATER RELAYS (2)
5 - RUBBER SHIELDS (4)
6 - CABLES TO BATTERY (+)
14 - 106 FUEL INJECTION - DIESELBR/BE
INTAKE AIR HEATER RELAY (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
TORQUE CONVERTER
LOCKS UP IN SECOND
AND/OR THIRD GEARLockup Solenoid, Relay or Wiring
Shorted/Open.Test solenoid, relay and wiring for
continuity, shorts or grounds. Replace
solenoid and relay if faulty. Repair wiring
and connectors as necessary.
HARSH 1-2, 2-3, 3-4 OR
3-2 SHIFTSLockup Solenoid Malfunction. Remove valve body and replace solenoid
assembly.
NO START IN PARK OR
NEUTRAL1. Gearshift Linkage/Cable
Mis-adjusted.1. Adjust linkage/cable.
2. Neutral Sense Wire Open/Cut. 2. Check continuity with test lamp. Repair
as required.
3. Park/Neutral Switch, or
Transmission Range Sensor Faulty.3. Refer to service section for test and
replacement procedure.
4. Park/Neutral Switch, or
Transmission Range Sensor
Connection Faulty.4. Connectors spread open. Repair.
5. Valve Body Manual Lever
Assembly Bent/Worn/Broken.5. Inspect lever assembly and replace if
damaged.
NO REVERSE (OR SLIPS
IN REVERSE)1. Direct Clutch Pack (front clutch)
Worn.1. Disassemble unit and rebuild clutch
pack.
2. Rear Band Mis-adjusted. 2. Adjust band.
3. Front Clutch Malfunctioned/
Burned.3. Air-pressure test clutch operation.
Remove and rebuild if necessary.
4. Overdrive Thrust Bearing Failure. 4. Disassemble geartrain and replace
bearings.
5. Direct Clutch Spring Collapsed/
Broken.5. Remove and disassemble unit. Check
clutch position and replace spring.
21 - 112 AUTOMATIC TRANSMISSION - 46REBR/BE
AUTOMATIC TRANSMISSION - 46RE (Continued)

GOVERNOR PRESSURE CURVES
There are four governor pressure curves pro-
grammed into the transmission control module. The
different curves allow the control module to adjust
governor pressure for varying conditions. One curve
is used for operation when fluid temperature is at, or
below, ±1ÉC (30ÉF). A second curve is used when fluid
temperature is at, or above, 10ÉC (50ÉF) during nor-
mal city or highway driving. A third curve is used
during wide-open throttle operation. The fourth curve
is used when driving with the transfer case in low
range.
OPERATION
Compensation is required for performance varia-
tions of two of the input devices. Though the slope of
the transfer functions is tightly controlled, offset may
vary due to various environmental factors or manu-
facturing tolerances.
The pressure transducer is affected by barometric
pressure as well as temperature. Calibration of the
zero pressure offset is required to compensate for
shifting output due to these factors.
Normal calibration will be performed when sump
temperature is above 50 degrees F, or in the absence
of sump temperature data, after the first 10 minutes
of vehicle operation. Calibration of the pressure
transducer offset occurs each time the output shaft
speed falls below 200 RPM. Calibration shall be
repeated each 3 seconds the output shaft speed is
below 200 RPM. A 0.5 second pulse of 95% duty cycle
is applied to the governor pressure solenoid valve
and the transducer output is read during this pulse.
Averaging of the transducer signal is necessary to
reject electrical noise.
Under cold conditions (below 50 degrees F sump),
the governor pressure solenoid valve response may
be too slow to guarantee 0 psi during the 0.5 second
calibration pulse. Calibration pulses are continued
during this period, however the transducer output
valves are discarded. Transducer offset must be read
at key-on, under conditions which promote a stable
reading. This value is retained and becomes the off-
set during the9cold9period of operation.
GOVERNOR PRESSURE SOLENOID VALVE
The inlet side of the solenoid valve is exposed to
normal transmission line pressure. The outlet side of
the valve leads to the valve body governor circuit.
The solenoid valve regulates line pressure to pro-
duce governor pressure. The average current sup-
plied to the solenoid controls governor pressure. One
amp current produces zero kPa/psi governor pres-
sure. Zero amps sets the maximum governor pres-
sure.The powertrain control module (PCM) turns on the
trans control relay which supplies electrical power to
the solenoid valve. Operating voltage is 12 volts
(DC). The PCM controls the ground side of the sole-
noid using the governor pressure solenoid control cir-
cuit.
GOVERNOR PRESSURE SENSOR
The sensor output signal provides the necessary
feedback to the PCM. This feedback is needed to ade-
quately control governor pressure.
GOVERNOR BODY AND TRANSFER PLATE
The transfer plate channels line pressure to the
solenoid valve through the governor body. It also
channels governor pressure from the solenoid valve
to the governor circuit. It is the solenoid valve that
develops the necessary governor pressure.
GOVERNOR PRESSURE CURVES
LOW TRANSMISSION FLUID TEMPERATURE
When the transmission fluid is cold the conven-
tional governor can delay shifts, resulting in higher
than normal shift speeds and harsh shifts. The elec-
tronically controlled low temperature governor pres-
sure curve is higher than normal to make the
transmission shift at normal speeds and sooner. The
PCM uses a temperature sensor in the transmission
oil sump to determine when low temperature gover-
nor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased
computing power of the PCM and through access to
data on engine operating conditions provided by the
PCM that were not available with the previous
stand-alone electronic module. This facilitated the
development of a load adaptive shift strategy - the
ability to alter the shift schedule in response to vehi-
cle load condition. One manifestation of this capabil-
ity is grade9hunting9prevention - the ability of the
transmission logic to delay an upshift on a grade if
the engine does not have sufficient power to main-
tain speed in the higher gear. The 3-2 downshift and
the potential for hunting between gears occurs with a
heavily loaded vehicle or on steep grades. When
hunting occurs, it is very objectionable because shifts
are frequent and accompanied by large changes in
noise and acceleration.
WIDE OPEN THROTTLE OPERATION
In wide-open throttle (WOT) mode, adaptive mem-
ory in the PCM assures that up-shifts occur at the
preprogrammed optimum speed. WOT operation is
determined from the throttle position sensor, which
is also a part of the emission control system. The ini-
BR/BEAUTOMATIC TRANSMISSION - 46RE 21 - 153
ELECTRONIC GOVERNOR (Continued)

²When in a manual selection position, it will be
hydraulically ªblockedº into position so no upshift can
occur.
The physical blocking of the upshift while in the
manual ª1º position is accomplished by the directing
of line pressure between both lands of the governor
plug. The line pressure reacts against the larger land
of the plug, pushing the plug back against the end
plate overcoming governor pressure. With the combi-
nation of the line pressure and spring pressure, the
valve cannot move, preventing any upshift.
1-2 SHIFT CONTROL VALVE
It contains a valve with four lands and a spring. It
is used as both a ªrelayº and ªbalancedº valve.
The valve has two specific operations (Fig. 260):
²Aid in quality of the 1-2 upshift.
²Aid in the quality and timing of the 3-2 kick-
down ranges.
When the manual valve is set to the DRIVE posi-
tion and the transmission is in the first or second
gear range, 1-2 shift control or ªmodulated throttle
pressureº is supplied to the middle of the accumula-
tor piston by the 1-2 shift control valve. During the
1-2 upshift, this pressure is used to control the kick-
down servo apply pressure that is needed to apply
the kickdown and accumulator pistons. Thus, the 1-2
shift point is ªcushionedº and the quality is
improved. During a WOT kickdown, kickdown pres-
sure is applied between the kickdown valve and the
1-2 shift control valve. This additional pressure is
directed to the 1-2 shift control's spring cavity, add-
ing to the spring load on the valve. The result of this
increased ªmodulatedº throttle pressure is a firmer
WOT upshift.
2-3 SHIFT VALVE
The 2-3 shift valve mechanism (Fig. 261) consists
of the 2-3 shift valve, governor plug and spring, anda throttle plug. After the 1-2 shift valve has com-
pleted its operation and applied the front band, line
pressure is directed to the 2-3 shift valve through the
connecting passages from the 1-2 shift valve. The line
pressure will then dead±end at land #2 until the 2-3
valve is ready to make its shift. Now that the vehicle
is in motion and under acceleration, there is throttle
pressure being applied to the spring side of the valve
and between lands #3 and #4.
As vehicle speed increases, governor pressure
increases proportionately, until it becomes great
enough to overcome the combined throttle and spring
pressure on the right side of the valve. Since the
throttle pressure end of the 2-3 shift valve is larger
in diameter than the 1-2 shift valve, the 2-3 shift will
always happen at a greater speed than the 1-2 shift.
When this happens, the governor plug is forced
against the shift valve moving it to the right. The
shift valve causes land #4 to close the passage sup-
plying throttle pressure to the 2-3 shift valve. With-
out throttle pressure present in the circuit now, the
governor plug will push the valve over far enough to
bottom the valve in its bore. This allows land #2 to
direct line pressure to the front clutch.
After the shift (Fig. 262), line pressure is directed
to the land between the shift valve and the governor
plug, and to the release side of the kickdown servo.
This releases the front band and applies the front
clutch, shifting into third gear or direct drive. The
rear clutch remains applied, as it has been in the
other gears. During a manual ª1º or manual ª2º gear
selection, line pressure is sent between the two lands
of the 2-3 governor plug. This line pressure at the
governor plug locks the shift valve into the second
gear position, preventing an upshift into direct drive.
The theory for the blocking of the valve is the same
as that of the 1-2 shift valve.
Fig. 259 1-2 Shift Valve-After Shift
BR/BEAUTOMATIC TRANSMISSION - 46RE 21 - 229
VALVE BODY (Continued)

Once the TCC control valve has moved to the right
(Fig. 267), line pressure is directed to the tip of the
switch valve, forcing the valve to the right. The
switch valve now vents oil from the front of the pis-
ton in the torque converter, and supplies line pres-
sure to the (rear) apply side of the torque converter
piston. This pressure differential causes the piston to
apply against the friction material, cutting off any
further flow of line pressure oil. After the switch
valve is shuttled right allowing line pressure to
engage the TCC, torque converter pressure is
directed past the switch valve into the transmission
cooler and lubrication circuits.MANUAL VALVE
The manual valve (Fig. 268) is a relay valve. The
purpose of the manual valve is to direct fluid to the
correct circuit needed for a specific gear or driving
range. The manual valve, as the name implies, is
manually operated by the driver with a lever located
on the side of the valve body. The valve is connected
mechanically by either a cable or linkage to the gear-
shift mechanism. The valve is held in each of its
positions by a spring-loaded roller or ball that
engages the ªroostercombº of the manual valve lever.
Fig. 267 Switch Valve-Torque Converter Locked
21 - 234 AUTOMATIC TRANSMISSION - 46REBR/BE
VALVE BODY (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
TORQUE CONVERTER
LOCKS UP IN SECOND
AND/OR THIRD GEARLockup Solenoid, Relay or Wiring
Shorted/Open.Test solenoid, relay and wiring for
continuity, shorts or grounds. Replace
solenoid and relay if faulty. Repair wiring
and connectors as necessary.
HARSH 1-2, 2-3, 3-4 OR
3-2 SHIFTSLockup Solenoid Malfunction. Remove valve body and replace solenoid
assembly.
NO START IN PARK OR
NEUTRAL1. Gearshift Linkage/Cable
Mis-adjusted.1. Adjust linkage/cable.
2. Neutral Sense Wire Open/Cut. 2. Check continuity with test lamp. Repair
as required.
3. Park/Neutral Switch, or
Transmission Range Sensor Faulty.3. Refer to service section for test and
replacement procedure.
4. Park/Neutral Switch, or
Transmission Range Sensor
Connection Faulty.4. Connectors spread open. Repair.
5. Valve Body Manual Lever
Assembly Bent/Worn/Broken.5. Inspect lever assembly and replace if
damaged.
NO REVERSE (OR SLIPS
IN REVERSE)1. Direct Clutch Pack (front clutch)
Worn.1. Disassemble unit and rebuild clutch
pack.
2. Rear Band Mis-adjusted. 2. Adjust band.
3. Front Clutch Malfunctioned/
Burned.3. Air-pressure test clutch operation.
Remove and rebuild if necessary.
4. Overdrive Thrust Bearing Failure. 4. Disassemble geartrain and replace
bearings.
5. Direct Clutch Spring Collapsed/
Broken.5. Remove and disassemble unit. Check
clutch position and replace spring.
21 - 284 AUTOMATIC TRANSMISSION - 47REBR/BE
AUTOMATIC TRANSMISSION - 47RE (Continued)

temperature is at, or above, 10ÉC (50ÉF) during nor-
mal city or highway driving. A third curve is used
during wide-open throttle operation. The fourth curve
is used when driving with the transfer case in low
range.
OPERATION
Compensation is required for performance varia-
tions of two of the input devices. Though the slope of
the transfer functions is tightly controlled, offset may
vary due to various environmental factors or manu-
facturing tolerances.
The pressure transducer is affected by barometric
pressure as well as temperature. Calibration of the
zero pressure offset is required to compensate for
shifting output due to these factors.
Normal calibration will be performed when sump
temperature is above 50 degrees F, or in the absence
of sump temperature data, after the first 10 minutes
of vehicle operation. Calibration of the pressure
transducer offset occurs each time the output shaft
speed falls below 200 RPM. Calibration shall be
repeated each 3 seconds the output shaft speed is
below 200 RPM. A 0.5 second pulse of 95% duty cycle
is applied to the governor pressure solenoid valve
and the transducer output is read during this pulse.
Averaging of the transducer signal is necessary to
reject electrical noise.
Under cold conditions (below 50 degrees F sump),
the governor pressure solenoid valve response may
be too slow to guarantee 0 psi during the 0.5 second
calibration pulse. Calibration pulses are continued
during this period, however the transducer output
valves are discarded. Transducer offset must be read
at key-on, under conditions which promote a stable
reading. This value is retained and becomes the off-
set during the9cold9period of operation.
GOVERNOR PRESSURE SOLENOID VALVE
The inlet side of the solenoid valve is exposed to
normal transmission line pressure. The outlet side of
the valve leads to the valve body governor circuit.
The solenoid valve regulates line pressure to pro-
duce governor pressure. The average current sup-
plied to the solenoid controls governor pressure. One
amp current produces zero kPa/psi governor pres-
sure. Zero amps sets the maximum governor pres-
sure.
The powertrain control module (PCM) turns on the
trans control relay which supplies electrical power to
the solenoid valve. Operating voltage is 12 volts
(DC). The PCM controls the ground side of the sole-
noid using the governor pressure solenoid control cir-
cuit.
GOVERNOR PRESSURE SENSOR
The sensor output signal provides the necessary
feedback to the PCM. This feedback is needed to ade-
quately control governor pressure.
GOVERNOR BODY AND TRANSFER PLATE
The transfer plate channels line pressure to the
solenoid valve through the governor body. It also
channels governor pressure from the solenoid valve
to the governor circuit. It is the solenoid valve that
develops the necessary governor pressure.
GOVERNOR PRESSURE CURVES
LOW TRANSMISSION FLUID TEMPERATURE
When the transmission fluid is cold the conven-
tional governor can delay shifts, resulting in higher
than normal shift speeds and harsh shifts. The elec-
tronically controlled low temperature governor pres-
sure curve is higher than normal to make the
transmission shift at normal speeds and sooner. The
PCM uses a temperature sensor in the transmission
oil sump to determine when low temperature gover-
nor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased
computing power of the PCM and through access to
data on engine operating conditions provided by the
PCM that were not available with the previous
stand-alone electronic module. This facilitated the
development of a load adaptive shift strategy - the
ability to alter the shift schedule in response to vehi-
cle load condition. One manifestation of this capabil-
ity is grade9hunting9prevention - the ability of the
transmission logic to delay an upshift on a grade if
the engine does not have sufficient power to main-
tain speed in the higher gear. The 3-2 downshift and
the potential for hunting between gears occurs with a
Fig. 70 Governor Pressure Sensor
1 - GOVERNOR BODY
2 - GOVERNOR PRESSURE SENSOR/TRANSMISSION FLUID
TEMPERATURE THERMISTOR
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 323
ELECTRONIC GOVERNOR (Continued)

1-2 SHIFT VALVE
The 1-2 shift valve assembly (Fig. 250), or mecha-
nism, consists of: the 1-2 shift valve, governor plug,
and a spring on the end of the valve. After the man-
ual valve has been placed into a forward gear range,
line pressure is directed to the 1-2 shift valve. As the
throttle is depressed, throttle pressure is applied to
the right side of the 1-2 shift valve assembly. With
throttle pressure applied to the right side of the
valve, there is now both spring pressure and throttle
pressure acting on the valve, holding it against the
governor plug. As the vehicle begins to move and
build speed, governor pressure is created and is
applied to the left of the valve at the governor plug.
When governor pressure builds to a point where it
can overcome the combined force of the spring and
throttle pressure on the other side of the valve, the
valve will begin to move over to the right. As the
valve moves to the right, the middle land of the valve
will close off the circuit supplying the throttle pres-
sure to the right side of the valve. When the throttlepressure is closed off, the valve will move even far-
ther to the right, allowing line pressure to enter
another circuit and energize the front servo, applying
the front band (Fig. 251).
The governor plug serves a dual purpose:
²It allows the shift valves to move either left or
right, allowing both upshifts and downshifts.
²When in a manual selection position, it will be
hydraulically ªblockedº into position so no upshift can
occur.
The physical blocking of the upshift while in the
manual ª1º position is accomplished by the directing
of line pressure between both lands of the governor
plug. The line pressure reacts against the larger land
of the plug, pushing the plug back against the end
plate overcoming governor pressure. With the combi-
nation of the line pressure and spring pressure, the
valve cannot move, preventing any upshift.
1-2 SHIFT CONTROL VALVE
It contains a valve with four lands and a spring. It
is used as both a ªrelayº and ªbalancedº valve.
Fig. 250 1-2 Shift Valve-Before Shift
Fig. 249 Kickdown Limit Valve-High Speeds
21 - 400 AUTOMATIC TRANSMISSION - 47REBR/BE
VALVE BODY (Continued)