DODGE RAM SRT-10 2006 Service Repair Manual

MODULE - FUEL TANK
DESCRIPTION
.
The fuel tank module is installed in the top of the fuel tank. The fuel tank module contains the following compo-
nents:
An electric fuel transfer (lift) pump
Fuel reservoir
A separate in-tank fuel filter
Fuel gauge sending unit (fuel level sensor)
Fuel supply line connection
A special lockring to retain module to fuel tank
Fuel return line connection
OPERATION
Refer to Fuel Gauge Sending Unit.
REMOVAL
1. Drain and remove fuel tank (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL TANK -
REMOVAL).
2. Note rotational position of module before attempt-
ing removal. An indexing arrow is located on top of
module for this purpose.
3. Position Special Tool 9340 (3) into notches on out-
side edge of lockring (5).
4. Install 1/2 inch drive breaker bar (1) to tool 9340
(3).
5. Rotate breaker bar counterclockwise to remove
lockring.
6. Remove lockring. The module will spring up slightly
when lockring is removed.
7. Remove module from fuel tank. Be careful not to
bend float arm while removing.
INSTALLATION
CAUTION: Whenever the fuel pump module is serviced, the rubber seal (gasket) must be replaced.

1. Using a new seal (gasket), position fuel pump mod-
uleintoopeninginfueltank.
2. Position lockring (5) over top of fuel pump module.
3. Rotate module until embossed alignment arrow
points to center alignment mark. This step must be
performed to prevent float from contacting side of
fuel tank. Also be sure fuel fitting on top of pump
module is pointed to drivers side of vehicle.
4. Install Special Tool 9340 (3) to lockring.
5. Install 1/2 inch drive breaker (1) into Special Tool
9340 (3).
6. Tighten lockring (clockwise) until all seven notches
have engaged.
7. Install fuel tank (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL TANK - INSTALLATION).

PUMP - FUEL TRANSFER
DESCRIPTION
The fuel transfer pump (fuel lift pump) is part of the fuel pump module. The fuel pump module is located in the fuel
tank. The 12–volt electric pump is operated and controlled by the Engine Control Module (ECM). The ECM controls
a relay in the Intelligent Power Module(IPM) for transfer pump operation.
OPERATION
The purpose of the fuel transfer pump is to supply (transfer) a low-pressure fuel source:fromthe fuel tank,through
the fuel filter/water separator andtothe fuel injection pump. Here, the low-pressure is raised to a high-pressure by
the fuel injection pump for operation of the high-pressure fuel injectors. Check valves within the pump, control direc-
tion of fuel flow and prevent fuel bleed-back during engine shut down.
Maximum current flow to the pump is 5 amperes.
With the engine running, the pump has a 100 percent duty-cycle.
The transfer pump is self-priming: When the key is first turned on (withoutcranking engine), the pump will operate
for approximately 2 seconds and then shut off (Note: When ambient temperatures are cold enough to cause the
intake air heaters to operate, the fuel lift pump will operate during the entire intake air pre-heat cycle). The pump will
also operate for up to 25 seconds after the starter is engaged, and then disengaged and the engine is not running.
The pump shuts off immediately if the key is on and the engine stops running.
The fuel volume of the transfer pump will always provide more fuel than the fuel injection pump requires. Excess
fuel is returned from the injection pump through an overflow valve, and then back to the fuel tank.
REMOVAL
The fuel transfer pump (fuel lift pump) is a part of the fuel tank module. It is not serviced separately. Refer to Fuel
Tank Module Removal or Installation for procedures (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/FUEL TANK
MODULE - REMOVAL).
INSTALLATION
The fuel transfer pump (fuel lift pump) is a part of the fuel tank module. It is not serviced separately (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL TANK MODULE - INSTALLATION).

VALVE - CASCADE OVERFLOW
DESCRIPTION
NOTE: The cascade overflow valve is not serviced separately.
Thecascadeoverflowvalve(4)islocatedonthetop/
rear side of the fuel injection pump.
OPERATION
When the fuel control actuator (FCA) is opened, the maximum amount of fuel is being delivered to the fuel injection
pump. The cascade valve regulates how much excess fuel is used for lubrication of the injection pump, and is also
used to route excess fuel through the drain circuit and back into the fuel tank.

SENSOR-WATER IN FUEL
DESCRIPTION
The Water-In-Fuel (WIF) sensor (5) is located on the
side of the fuel filter/water separator canister.
OPERATION
The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter/water sep-
arator. As the water level in the filter/separator increases, the resistance across the WIF sensor decreases. This
decreaseinresistanceissentasasignaltotheECMandcomparedtoahighwater standard value. Once the value
reaches 30 to 40 kilohms, the ECM will activate the water-in-fuel warning lamp through CCD bus circuits. This all
takes place when the ignition key is initially put in the ON position. The ECM continues to monitor the input while
the engine is running.
REMOVAL
The Water-In-Fuel (WIF) sensor is located at the side of fuel filter/waterseparator canister. (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL TANK MODULE - INSTALLATION).

CIRCUIT - FUEL DRAIN
OPERATION
The Fuel Drain Circuit incorporates several sources of fuel return. Fuel travels from the fuel tank (via the fuel trans-
fer pump) and is forced through the fuel filter. This fuel then travels intothe fuel injection pump. It then goes to a
fuel drain line and returns back to the fuel tank.
The fuel that flows to the fuel pump is pressurized by a gear pump and internally transferred to the fuel injection
pump. At this point the fuel is channeled into two passages. One passage sends fuel to the FCA (Fuel Control
Actuator). The other passage sends fuel to the cascade overflow valve. Theoverflow valve sends some fuel to a
lubrication passage. The rest of the fuel is sent to a drain passage which connects to an external fuel line.
Fuel that travels through the FCA is pressurized by the fuel injection pumpand sent through an external high pres-
sure fuel line to the fuel rail. At the fuel rail, fuel is sent to the fuel injectors. If fuel pressure in the fuel rail becomes
excessive, the pressure limiting valve opens and sends fuel through an external fuel line.
At the fuel injector, fuel that is not injected is used for lubrication of the fuel injectors. This fuel then travels through
an internal passage that is connected to the rear of the cylinder head, an then into an external fuel line. This line is
connected to the vehicles fuel return line, and returns excess fuel back and into the fuel tank.

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SENSOR-ACCELERATOR PEDAL POSITION
DESCRIPTION ............................... 141
OPERATION ................................. 141
REMOVAL ................................... 141
INSTALLATION .............................. 142
SENSOR-CAMSHAFT POSITION
DESCRIPTION ............................... 143
OPERATION ................................. 143
REMOVAL ................................... 143
INSTALLATION .............................. 144
SENSOR-CRANKSHAFT POSITION
DESCRIPTION ............................... 145
OPERATION ................................. 145
REMOVAL ................................... 146
INSTALLATION .............................. 146
ACTUATOR - FUEL CONTROL
DESCRIPTION ............................... 147
OPERATION ................................. 147
REMOVAL ................................... 147
INSTALLATION .............................. 147
INJECTOR - FUEL
DESCRIPTION ............................... 148
OPERATION ................................. 149
REMOVAL ................................... 149
INSTALLATION .............................. 153
FUEL INJECTOR RAIL
DESCRIPTION ............................... 155
OPERATION ................................. 155REMOVAL ................................... 155
INSTALLATION .............................. 156
SENSOR-TEMPERATURE/PRESSURE-INTAKE
DESCRIPTION ............................... 157
OPERATION ................................. 157
REMOVAL ................................... 157
INSTALLATION .............................. 159
HEATER - INTAKE AIR
DESCRIPTION ............................... 160
OPERATION ................................. 160
REMOVAL ................................... 160
INSTALLATION .............................. 162
RELAY - INTAKE AIR HEATER
DESCRIPTION ............................... 163
OPERATION ................................. 163
REMOVAL ................................... 163
INSTALLATION .............................. 164
SENSOR-TEMPERATURE/PRESSURE-MAP
DESCRIPTION ............................... 165
OPERATION ................................. 165
REMOVAL ................................... 165
INSTALLATION .............................. 166
SENSOR-MAP
DESCRIPTION ............................... 167
SWITCH - PTO
DESCRIPTION ............................... 168
OPERATION ................................. 168

SENSOR-ACCELERATOR PEDAL POSITION
DESCRIPTION
The Accelerator Pedal Position Sensor (APPS) (1) is
located inside the vehicle.It is attached to the accel-
erator pedal assembly (3).
OPERATION
The Accelerator Pedal Position Sensor (APPS) provides the Engine ControlModule (ECM) with two DC voltage
signals which change as the position of the accelerator pedal changes. Oneof the DC voltage signals will be half
the voltage of the other signal.
REMOVAL
CAUTION: Do not attempt to separate or remove the Accelerator Pedal Position Sensor (APPS) from the
accelerator pedal assembly. The APPS is replaced as an assembly along withthe pedal. If sensor is
removed from pedal, its electronic calibration may be destroyed.
1. Disconnect 6–way electrical connector at top of
APPS (2).
2. Remove APPS lower mounting bolt (4) and two
mounting nuts.
3. Remove pedal and APPS assembly from vehicle.

INSTALLATION
CAUTION: Do not attempt to separate or remove the Accelerator Pedal Position Sensor (APPS) from the
accelerator pedal assembly. The APPS is replaced as an assembly along withthe pedal. If sensor is
removed from pedal, its electronic calibration may be destroyed.
1. Position pedal and APPS assembly to its mounting
bracket.
2. Connect 6–way electrical connector to top of APPS
(2).
3. Install APPS lower mounting bolt (4) and two
mounting nuts.
4. If necessary, use a Scan Tool to erase any Diag-
nostic Trouble Codes (DTC’s).

SENSOR-CAMSHAFT POSITION
DESCRIPTION
The Camshaft Position Sensor (CMP) on the 5.9L diesel engine is located below the fuel injection pump. It is bolted
to the back of the timing gear housing.
OPERATION
The diesel Camshaft Position Sensor (CMP) contains
a hall effect device. A rotating target wheel (tone-
wheel) for the CMP is located on the camshaft gear.
This hall effect device detects holes located on the
back side of the camshaft gear. As the camshaft gear
rotates, the holes pass the tip of the CMP.
When the leading edge of the hole passes the tip of
the CMP, the following occurs: The interruption of
magnetic field causes the voltage to switch high
resulting in a signal of approximately 5 volts.
When the trailing edge of the hole passes the tip of
the CMP, the following occurs: The change of the
magnetic field causes the signal voltage to switch low
to 0 volts.
The CMP (1) provides a signal to the Engine Control
Module (ECM) at all times when the engine is running.
TheECMusestheCMPinformationprimarilyon
engine start-up. Once the engine is running, the ECM
uses the CMP as a backup sensor for engine speed.
The Crankshaft Position Sensor (CKP) is the primary
engine speed indicator for the engine after the engine
is running.
REMOVAL
The Camshaft Position Sensor (CMP) on the 5.9L die-
sel engine is located (1) below the fuel injection pump.
It is bolted to the back of the timing gear housing (7).
1. Disconnect electrical connector at CMP sensor.
2. Remove sensor mounting bolt (6).
3. Carefully twist and pull the sensor from timing gear
housing.
4. Check condition of sensor O-ring.