relay DODGE RAM 2001 Service Repair Manual

FUEL INJECTION - DIESEL
TABLE OF CONTENTS
page page
FUEL INJECTION - DIESEL
DESCRIPTION...........................87
DIAGNOSIS AND TESTING.................89
BOOST PRESSURE.....................89
SPECIFICATIONS........................90
ACCELERATOR PEDAL POSITION SENSOR
DESCRIPTION...........................91
OPERATION.............................91
REMOVAL..............................91
INSTALLATION...........................93
FUEL INJECTOR
DESCRIPTION...........................93
OPERATION.............................94
DIAGNOSIS AND TESTING.................95
FUEL INJECTOR TEST...................95
REMOVAL..............................96
INSTALLATION...........................98
FUEL INJECTION PUMP RELAY
DESCRIPTION...........................99
OPERATION.............................99
FUEL TEMPERATURE SENSOR
DESCRIPTION...........................99
OPERATION............................100
INTAKE AIR HEATER
DESCRIPTION..........................100OPERATION............................100
REMOVAL.............................100
INSTALLATION..........................101
INTAKE AIR HEATER RELAY
DESCRIPTION..........................101
OPERATION............................102
REMOVAL.............................102
INSTALLATION..........................102
INTAKE AIR TEMPERATURE SENSOR
DESCRIPTION..........................102
OPERATION............................102
REMOVAL.............................103
INSTALLATION..........................103
MAP SENSOR
DESCRIPTION..........................103
OPERATION............................103
REMOVAL.............................104
INSTALLATION..........................104
PTO SWITCH
DESCRIPTION..........................104
THROTTLE CONTROL CABLE
REMOVAL.............................104
INSTALLATION..........................105
FUEL INJECTION - DIESEL
DESCRIPTION - DIESEL FUEL INJECTION
SYSTEM
The Engine Control Module (ECM) and Fuel Injec-
tion Pump Control Module (FPCM) are used prima-
rily for fuel system control. The ECM is a separate
replaceable component, while the FPCM is internal
to the fuel injection pump and is a non-serviceable
part. The ECM and FPCM are interconnected (wired
together) for fuel injection control.The Powertrain Control Module (PCM) is used to
regulate or control the A/C, charging and speed con-
trol systems. It is also used to partially control cer-
tain electronic automatic transmission components.
The PCM also has control over certain instrument
panel components.
Refer to either Powertrain Control Module (PCM)
or Engine Control Module (ECM) for additional infor-
mation. Refer to (Fig. 1) for a partial list of fuel sys-
tem components.
BR/BEFUEL INJECTION - DIESEL 14 - 87

SPECIFICATIONS
TORQUE - DIESEL ENGINE
DESCRIPTION N m Ft. Lbs. In. Lbs.
Accelerator Pedal Position Sensor
Bracket Bolts12 105
Air Intake Housing Bolts 24 18
Banjo Fittings at top of Filter/Separator 24 18
Banjo Fittings at Fuel Return Lines 24 18
Banjo Fitting At Fuel Supply Line
(Injector Pump)24 18
Camshaft Position Sensor (CMP) Bolt 20 15
ECM Mounting Bolts 24 18
Engine Coolant Temperature (ECT)
Sensor14 10
Engine Lifting Bracket Bolts 77 57
Fuel Drain Manifold ªTº Fitting 12 106
Fuel Filter Canister Bracket Bolts 24 18
Fuel Filter Canister Mounting Nut 14 10
Fuel Filter Drain Valve Mounting
Screws3-5 30-40
Fuel Heater Screws 2-3 15-20
Fuel Injector Clamp Bolts 10 89
Fuel Pump Module Locknut 24-44 18-32
Fuel Tank Mounting Nuts 41 30
Fuel Transfer Pump Mounting Nuts 12 9
High-Pressure Fuel Line Fittings (at
Injectors)38 28
High-Pressure Fuel Line Fittings (at
Pump)24 18
High-Pressure Fuel Line Clamps-to-
Intake Manifold24 18
Hose Clamps at Intercooler Tube 8 72
Injection Pump-to-Injection Pump Gear
Nut170 125
Injection Pump Mounting Nuts 43 32
Intake Manifold Air Temperature (IAT)
Sensor14 10
Intake Manifold Air Heater Relay Bolts 4.5 40
Manifold Air Pressure (MAP) Sensor 14 10
PCM Mounting Bolts 4 35
Overflow Valve-to-Fuel Injection Pump 24 18
Water-In-Fuel (WIF) Sensor 2-3 15-20
14 - 90 FUEL INJECTION - DIESELBR/BE
FUEL INJECTION - DIESEL (Continued)

(g) If any of these conditions occur, replace injec-
tor.
(2) Thoroughly clean fuel injector cylinder head
bore with special Cummins wire brush tool or equiv-
alent (Fig. 24). Blow out bore hole with compressed
air.
(3) The bottom of fuel injector is sealed to cylinder
head bore with a copper sealing washer (shim) of a
certain thickness. A new shim with correct thickness
must always be re-installed after removing injector.
Measure thickness of injector shim (Fig. 23).Shim
Thickness: 1.5 mm (.060º)
(4) Install new shim (washer) to bottom of injector
(Fig. 22). Apply light coating of clean engine oil to
washer. This will keep washer in place during instal-
lation.
(5) Install new o-ring to fuel injector. Apply small
amount of clean engine oil to o-ring.
(6) Note fuel inlet hole on side of fuel injector. This
hole must be positioned towards injector connector
tube. Position injector into cylinder head bore being
extremely careful not to allow injector tip to touch
sides of bore. Press fuel injector into cylinder head
with finger pressure only.Do not use any tools to
press fuel injector into position. Damage to
machined surfaces may result.
(7) Position fuel injector hold down clamp into
shouldered bolt while aligning slot in top of injector
into groove in bottom of clamp. Tighten opposite
clamp bolt (Fig. 18) to 10 N´m (89 in. lbs.) torque.
(8) Install new o-ring to fuel injector connector
tube. Apply small amount of clean engine oil to
o-ring.
(9) Press injector connector tube into cylinder head
with finger pressure only.Do not use any tools topress tube into position. Damage to machined
surfaces may result.
(10) Connect high-pressure fuel lines. Refer to
High-Pressure Fuel Lines Removal/Installation.The
fuel line fitting torque is very critical.If fitting
is under torqued, the mating surfaces will not seal
and a high-pressure fuel leak will result. If fitting is
over torqued, the connector and injector will deform
and also cause a high-pressure fuel leak. This leak
will be inside cylinder head and will not be visible
resulting in a possible fuel injector miss and low
power.
(11) Install valve cover. (Refer to 9 - ENGINE/
CYLINDER HEAD/CYLINDER HEAD COVER(S) -
INSTALLATION).
(12) (If necessary) install intake manifold air
heater assembly. Refer to Intake Manifold Air Heater
Removal/Installation.
(13) (If necessary) install engine lifting bracket.
Tighten 2 bolts to 77 N´m (57 ft. lbs.) torque.
(14) Connect negative battery cables to both bat-
teries.
(15) Bleed air from high-pressure lines (Refer to 14
- FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE).
FUEL INJECTION PUMP
RELAY
DESCRIPTION
The fuel injection pump relay is located in the
Power Distribution Center (PDC). Refer to label
under PDC cover for relay location.
OPERATION
The Engine Control Module (ECM) energizes the
electric fuel injection pump through the fuel injection
pump relay. Battery voltage is applied to the fuel
injection pump relay at all times. When the key is
turned ON, the relay is energized when a 12±volt sig-
nal is provided by the ECM. When energized,
12±volts is supplied to the Fuel Pump Control Mod-
ule. The Fuel Pump Control Module is located on the
top of the fuel injection pump and is non-servicable.
FUEL TEMPERATURE SENSOR
DESCRIPTION
Two different fuel temperature sensors are used.
One of the sensors is located inside of the Bosch
VP44 fuel injection pump and is a non-serviceable
part. The other fuel temperature sensor is located in
the top of the fuel filter housing and is serviceable
(serviceable if replacing the fuel heater).
Fig. 24 Cleaning Cylinder Head Injector BoreÐ
TYPICAL BORE
1 - INJECTOR BORE
2 - WIRE BRUSH
BR/BEFUEL INJECTION - DIESEL 14 - 99
FUEL INJECTOR (Continued)

OPERATION
The sensor located in the Bosch VP44 fuel injection
pump is used to check fuel temperature within the
injection pump and to set a Diagnostic Trouble Code
(DTC) if a specific high fuel temperature has been
reached. If high temperature has been reached,
engine power will be de-rated by the Engine Control
Module (ECM).
The sensor located in the top of the fuel filter hous-
ing is used to control the fuel heater element. Refer
to Fuel Heater Description and Operation for addi-
tional information.
INTAKE AIR HEATER
DESCRIPTION
The intake manifold air heater element assembly
is located in the top of the intake manifold (Fig. 25).
OPERATION
The air heater elements are used to heat incoming
air to the intake manifold. This is done to help
engine starting and improve driveability with cool or
cold outside temperatures.
Electrical supply for the 2 air heater elements is
controlled by the Engine Control Module (ECM)
through the 2 air heater relays. Refer to Intake Man-
ifold Air Heater Relays for more information.
Two heavy-duty cables connect the 2 air heater ele-
ments to the 2 air heater relays. Each of these cables will
supply approximately 95 amps at 12 volts to an individ-
ual heating element within the heater block assembly.
Refer to the Powertrain Diagnostic Procedures
manual for an electrical operation and complete
description of the intake heaters, including pre-heat
and post-heat cycles.
REMOVAL
The 2 intake manifold air heater elements are
attached to a metal block located at the top of the
intake manifold (Fig. 26). If servicing either of the
heater elements, the entire block/element assembly
must be replaced.
(1) Disconnect both negative battery cables at both
batteries.
(2) Disconnect clamp from rubber hose at air
intake housing.
(3) Disconnect rubber hose at air intake housing.
(4) Remove engine oil dipstick tube mounting bolt
(Fig. 28). Position dipstick tube to the side.
(5) Disconnect heater electrical cables at cable
mounting studs (Fig. 28).
(6) Disconnect ground cable bolt and ground cable
from housing (Fig. 27).
(7) Remove 4 housing bolts (Fig. 28).
(8) Remove air intake housing from top of heater
elements.
(9) Remove heater element assembly from intake
manifold.
(10) Clean old gasket material from air intake
housing and intake manifold.
(11) Clean old gasket material from both ends of
heater block (Fig. 26).
Fig. 25 Air Heater Elements Location
1 - AIR HEATER ELEMENTS
2 - LOWER GASKET
3 - BLOCK
4 - UPPER GASKET
Fig. 26 Intake Manifold Air Heater Element Location
1 - AIR HEATER ELEMENTS
2 - LOWER GASKET
3 - BLOCK
4 - UPPER GASKET
14 - 100 FUEL INJECTION - DIESELBR/BE
FUEL TEMPERATURE SENSOR (Continued)

INSTALLATION
The 2 intake manifold air heater elements are
attached to a metal block located at the top of theintake manifold (Fig. 26). If servicing either of the
heater elements, the entire block/element assembly
must be replaced.
(1) Using 2 new gaskets, position element assem-
bly and air housing to intake manifold.
(2) Position ground cable (Fig. 27) to air housing.
(3) Install 4 housing bolts and tighten to 24 N´m
(18 ft. lbs.) torque.
(4) Connect heater cables at cable mounting studs
(Fig. 28).Do not allow the cable eyelets to con-
tact any other metal source other than the
cable nuts/studs.
(5)
Install engine oil dipstick tube and mounting bolt.
(6) Connect rubber hose to air intake housing.
(7) Connect clamp to rubber hose at air intake
housing.
(8) Connect both negative battery cables at both
batteries.
INTAKE AIR HEATER RELAY
DESCRIPTION
The 2 intake manifold air heater relays are located
in the engine compartment, attached to the left inner
fender below the left battery (Fig. 29).
Fig. 27 Air Intake Housing (Front View)
1 - GROUND CABLE BOLT
2 - INTAKE AIR HOUSING
3 - CABLE BRACKET HOUSING BOLTS (3)
4 - GROUND CABLE
Fig. 28 Air Intake Housing (Rear View)
1 - TUBE MOUNTING BOLT
2 - HOUSING BOLTS (2)
3 - INTAKE HEATER CABLE MOUNTING STUDS (2)
4 - DIPSTICK TUBEFig. 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 (+)
BR/BEFUEL INJECTION - DIESEL 14 - 101
INTAKE AIR HEATER (Continued)

OPERATION
The Engine Control Module (ECM) operates the 2
heating elements through the 2 intake manifold air
heater relays.
Refer to Powertrain Diagnostic Procedures for an
electrical operation and complete description of the
intake heaters, including pre-heat and post-heat
cycles.
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. 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 (+)
Fig. 31 Intake Manifold Air Temperature (IAT) Sensor
Location
1 - MANIFOLD AIR PRESSURE (MAP) SENSOR
2 - REAR OF CYLINDER HEAD
3 - IAT SENSOR
4 - ELECTRICAL CONNECTOR
5 - ELECTRICAL CONNECTOR
14 - 102 FUEL INJECTION - DIESELBR/BE
INTAKE AIR HEATER RELAY (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
SLIPS IN OVERDRIVE
FOURTH GEAR1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Overdrive Clutch Pack Worn. 2. Remove overdrive unit and rebuild clutch
pack.
3. Overdrive Piston Retainer Bleed
Orifice Blown Out.3. Disassemble transmission, remove
retainer and replace orifice.
4. Overdrive Piston or Seal
Malfunction.4. Remove overdrive unit. Replace seals if
worn. Replace piston if damaged. If piston
retainer is damaged, remove and
disassemble the transmission.
5. 3-4 Shift Valve, Timing Valve or
Accumulator Malfunction.5. Remove and overhaul valve body.
Replace accumulator seals. Make sure all
valves operate freely in bores and do not
bind or stick. Make sure valve body screws
are correctly tightened and separator plates
are properly positioned.
6. Overdrive Unit Thrust Bearing
Failure.6. Disassemble overdrive unit and replace
thrust bearing (NO. 1 thrust bearing is
between overdrive piston and clutch hub;
NO. 2 thrust bearing is between the
planetary gear and the direct clutch spring
plate; NO. 3 thrust bearing is between
overrunning clutch hub and output shaft).
7. O/D Check Valve/Bleed Orifice
Failure.7. Check for function/secure orifice insert in
O/D piston retainer.
DELAYED 3-4 UPSHIFT
(SLOW TO ENGAGE)1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Throttle Valve Cable Mis-adjusted. 2. Adjust throttle valve cable.
3. Overdrive Clutch Pack Worn/
Burnt.3. Remove unit and rebuild clutch pack.
4. TPS Faulty. 4. Test with DRBTscan tool and replace as
necessary
5. Overdrive Clutch Bleed Orifice
Plugged.5. Disassemble transmission and replace
orifice.
6. Overdrive Solenoid or Wiring
Shorted/Open.6. Test solenoid and check wiring for
loose/corroded connections or shorts/
grounds. Replace solenoid if faulty and
repair wiring if necessary.
7. Overdrive Excess Clearance. 7. Remove unit. Measure end play and
select proper spacer.
8. O/D Check Valve Missing or
Stuck.8. Check for presence of check valve.
Repair or replace as required.
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.
BR/BEAUTOMATIC TRANSMISSION - 42RE 21 - 157
AUTOMATIC TRANSMISSION - 42RE (Continued)

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-
tial setting for the WOT upshift is below the opti-
mum engine speed. As WOT shifts are repeated, the
PCM learns the time required to complete the shifts
by comparing the engine speed when the shifts occur
to the optimum speed. After each shift, the PCM
adjusts the shift point until the optimum speed is
reached. The PCM also considers vehicle loading,
grade and engine performance changes due to high
altitude in determining when to make WOT shifts. It
does this by measuring vehicle and engine accelera-
tion and then factoring in the shift time.
TRANSFER CASE LOW RANGE OPERATION
On four-wheel drive vehicles operating in low
range, the engine can accelerate to its peak more
rapidly than in Normal range, resulting in delayed
shifts and undesirable engine9flare.9The low range
governor pressure curve is also higher than normal
to initiate upshifts sooner. The PCM compares elec-
tronic vehicle speed signal used by the speedometer
to the transmission output shaft speed signal to
determine when the transfer case is in low range.
BR/BEAUTOMATIC TRANSMISSION - 42RE 21 - 195
ELECTRONIC GOVERNOR (Continued)

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. 257):
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 position
and the transmission is in the first or second gear range,
1-2 shift control or ªmodulated throttle pressureº is sup-
plied to the middle of the accumulator piston by the 1-2
shift control valve. During the 1-2 upshift, this pressure
is used to control the kickdown servo apply pressure that
is needed to apply the kickdown and accumulator pis-
tons. Thus, the 1-2 shift point is ªcushionedº and the
quality is improved. During a WOT kickdown, kickdown
pressure 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, adding 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. 258) consists of
the 2-3 shift valve, governor plug and spring, and a
throttle plug. After the 1-2 shift valve has completed 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 andunder 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 pres-
sure 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 mov-
ing it to the right. The shift valve causes land #4 to
close the passage supplying throttle pressure to the 2-3
shift valve. Without throttle pressure present in the cir-
cuit 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. 259), 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. 257 1-2 Shift Control Valve
21 - 274 AUTOMATIC TRANSMISSION - 42REBR/BE
VALVE BODY (Continued)

MANUAL VALVE
The manual valve (Fig. 265) 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.
CONVERTER CLUTCH LOCK-UP VALVE
The torque converter clutch (TCC) lock-up valve
controls the back (ON) side of the torque converter
clutch. When the PCM energizes the TCC solenoid to
engage the converter clutch piston, pressure is
applied to the TCC lock-up valve which moves to the
right and applies pressure to the torque converter
clutch.
CONVERTER CLUTCH LOCK-UP TIMING VALVE
The torque converter clutch (TCC) lock-up timing
valve is there to block any 4-3 downshift until the
TCC is completely unlocked and the clutch is disen-
gaged.
SHUTTLE VALVE
The assembly is contained in a bore in the valve
body above the shift valves. When the manual valve
is positioned in the Drive range, throttle pressure
acts on the throttle plug of the shuttle valve (Fig.
257) to move it against a spring, increasing the
spring force on the shuttle valve. During a part or
full throttle 1-2 upshift, the throttle plug is bottomed
by throttle pressure, holding the shuttle valve to the
right against governor pressure, and opening a
by±pass circuit. The shuttle valve controls the qual-
ity of the kickdown shift by restricting the rate of
fluid discharge from the front clutch and servo
release circuits. During a 3-2 kickdown, fluid dis-
charges through the shuttle by-pass circuit. When
the shuttle valve closes the by-pass circuit, fluid dis-
charge is restricted and controlled for the application
of the front band. During a 2-3 ªlift footº upshift, the
shuttle valve by-passes the restriction to allow full
fluid flow through the by-pass groove for a faster
release of the band.
Fig. 265 Manual Valve
21 - 280 AUTOMATIC TRANSMISSION - 42REBR/BE
VALVE BODY (Continued)