2006 DODGE RAM SRT-10 check engine

1. Position the A/C compressor (2) onto the accessory
mounting bracket (4).
2. Install and tighten the bolts in the following
sequence:
Install bolt (3) and hand tighten.
Install bolt (6) and hand tighten.
Install bolt (1) and hand tighten.
Tightened bolt (3) to 40 Nꞏm (30 ft. lbs.).
Tightened bolt (6) to 55 Nꞏm (41 ft. lbs.).
Tightened bolt (1) to 55 Nꞏm (41 ft. lbs.).
Tightened bolt (5) to 55 Nꞏm (41 ft. lbs.).
3. Remove the tape or plugs from the opened refrig-
erant line fittings and the compressor ports.
4. Lubricate new seals with clean refrigerant oil and
install them onto the refrigerant line fittings. Use
only the specified seals as they are made of a spe-
cial material for the R-134a system. Use only
refrigerant oil of the type recommended for the A/C
compressor in the vehicle.
5. Install the A/C suction line (5) and the A/C dis-
charge line (9) onto the A/C compressor (6).
6. Install the nuts (4) that secure the refrigerant lines
to the A/C compressor. Tighten the nuts to 20 Nꞏm
(15 ft. lbs.).
7. Install the accessory drive belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/BELTS-DRIVE - INSTAL-
LATION).
8. Reconnect the negative battery cable.
9. Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE).
10. Charge the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM CHARGE).
5.7L ENGINE
NOTE: Be certain to check the refrigerant oil level if the A/C compressor isbeing replaced. See Refrigerant
Oil Level in this group for the procedures. Use only refrigerant oil of the type recommended for the A/C
compressor in the vehicle.

1. Position the A/C compressor (2) into the engine
compartment.
2. Install and tighten the bolts that secure the A/C
compressor to the mounting bracket (4) in the fol-
lowing sequence:
Install the two lower bolts (1) and hand tighten.
Install the rear bolt (3) and hand tighten.
Tightenthetwolowerboltsto40Nꞏm(30ft.
lbs.).
Tighten the rear bolt to 55 Nꞏm (41 ft. lbs.).
3. Install the generator support bracket (Refer to 8 -
ELECTRICAL/CHARGING/GENERATOR -
INSTALLATION).
4. Remove the tape or plugs from the opened refrig-
erant line fittings and the compressor ports.
5. Lubricate new O-rings and dual plane seals with
clean refrigerant oil and install them onto the refrig-
erant line fittings. Use only the specified seals as
they are made of a special material for the R-134a
system. Use only refrigerant oil of the type recom-
mended for the A/C compressor in the vehicle.
6. Install the A/C discharge line (1) and the A/C suc-
tion line (5) onto the A/C compressor (6).
7. Install the nuts (4 and 7) that secure the refrigerant
lines to the A/C compressor. Tighten the nuts to 20
Nꞏm (15 ft. lbs.).
8. Connect the wire harness connector to the clutch
field coil connector and the A/C pressure trans-
ducer (8).
9. Install the accessory drive belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/BELTS-DRIVE - INSTAL-
LATION).
10. Reconnect the negative battery cable.
11. Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - STANDARD PROCEDURE - REFRIGERANT SYSTEM EVAC-
UATE).
12. Charge the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM CHARGE).
5.9L DIESEL ENGINE
NOTE: Be certain to check the refrigerant oil level if the A/C compressor isbeing replaced. See Refrigerant
Oil Level in this group for the procedures. Use only refrigerant oil of the type recommended for the A/C
compressor in the vehicle.

1. Position the A/C compressor (2) onto the mounting
bracket (3) located on the right side of the cylinder
block (4).
2. Install and hand tighten the four bolts (1) that
secure the A/C compressor to the mounting
bracket.
3. Tighten the bolts that secure the A/C compressor to
themountingbracketto23Nꞏm(17ft.lbs.).
4. Remove the tape or plugs from the opened refrig-
erant line fittings and the compressor ports.
5. Lubricate new seals with clean refrigerant oil and
install them onto the refrigerant line fittings. Use
only the specified seals as they are made of a spe-
cial material for the R-134a system. Use only
refrigerant oil of the type recommended for the A/C
compressor in the vehicle.
6. Install the A/C suction and discharge line assembly
(2) onto the A/C compressor (3).
7. Install the bolt (1) that secures the refrigerant line
assembly to the A/C compressor. Tighten the bolt
to 23 Nꞏm (17 ft. lbs.).
8. Connect the wire harness to the clutch field coil
wire lead connector (4).
9. Install the accessory drive belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/BELTS-DRIVE - INSTAL-
LATION).
10. Reconnect the negative battery cable.
11. Evacuate the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD
PROCEDURE - REFRIGERANT SYSTEM EVACUATE).
12. Charge the refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM CHARGE).
8.3L ENGINE
NOTE: Be certain to check the refrigerant oil level if the A/C compressor isbeing replaced. See Refrigerant
Oil Level in this group for the procedures. Use only refrigerant oil of the type recommended for the A/C
compressor in the vehicle.

OIL-A/C REFRIGERANT
DESCRIPTION
The refrigerant oil used in R-134a refrigerant systems is a synthetic-based, polyalkylene glycol (PAG), wax-free
lubricant. Mineral-based R-12 refrigerant oils are not compatible with PAG oils, and should never be introduced to
an R-134a refrigerant system.
There are different PAG oils available, and each contains a different additive package. Useonlyrefrigerant oil of the
same type as recommended to service the refrigerant system (always refer to the specification tagincluded with
the replacement A/C compressor or the A/C Underhood Specification Label located in the engine compartment).
The Denso 10S17 A/C compressor used in this vehicle when equipped with the 3.7L, 4.7L, 5.7L or 8.3L engine is
designed to use ND-8 PAG refrigerant oil. Use only this type of refrigerantoil when servicing the A/C compressor for
these engines.
The Visteon HS-18 A/C compressor used in this vehicle when equipped with 5.9L diesel engine is designed to use
VC-46 PAG refrigerant oil. Use only this type of refrigerant oil when servicing this A/C compressor.
OPERATION
After performing any refrigerant recovery or recycling operation, always replenish the refrigerant system with the
same amount of the recommended refrigerant oil as was removed. Too little refrigerant oil can cause A/C compres-
sor damage, and too much can reduce A/C system performance.
PAG refrigerant oil is more hygroscopic than mineral oil, and will absorb any moisture it comes into contact with,
even moisture in the air. The PAG oil container should always be kept tightly capped until it is ready to be used.
After use, recap the oil container immediately to prevent moisture contamination.
STANDARD PROCEDURE
REFRIGERANT OIL LEVEL
When an A/C system is assembled at the factory, all components except the A/C compressor are refrigerant oil free.
After the refrigerant system has been charged and operated, the refrigerant oil in the A/C compressor is dispersed
throughout the refrigerant system. The accumulator, A/C evaporator, A/Ccondenser and the A/C compressor will
each retain a significant amount of the needed refrigerant oil.
It is important to have the correct amount of refrigerant oil in the A/C system. This ensures proper lubrication of the
A/C compressor. Too little oil will result in damage to the A/C compressor,while too much oil will reduce the cooling
capacity of the A/C system and consequently result in higher discharge airtemperatures.
CAUTION: The refrigerant oil in the R-134a A/C system is unique depending on the A/C compressor used.
Use only PAG oils that are designed to work with R-134a refrigerant and the A/C compressor in the vehicle.
Always refer to the A/C Underhood Specification Label for the correct oil designation. The oil container
should be kept tightly capped until it is ready for use and then tightly capped after use to prevent contam-
ination from dirt and moisture. Refrigerant oil will quickly absorb any moisture it comes in contact with,
therefore, special effort must be used to keep all R-134a system components moisture-free. Moisture in the
refrigerant oil is very difficult toremove and will cause a reliability problem with the A/C compressor.
NOTE: Most reclaim/recycling equipment will measure the lubricant beingremoved during recovery. This
amount of lubricant should be added back into the system. Refer to the reclaim/recycling equipment man-
ufacturers instructions.
It will not be necessary to check the oil level in the A/C compressor or to addoil, unless there has been an oil loss.
An oil loss may occur due to a rupture or leak from a refrigerant line, a connector fitting, a component, or a com-
ponent seal. If a leak occurs, add 30 milliliters (1 fluid ounce) of refrigerant oil to the refrigerant system after the
repair has been made. Refrigerant oil loss will be evident at the leak pointby the presence of a wet, shiny surface
around the leak.
Refrigerant oil must be added when an accumulator, A/C evaporator or A/C condenser is replaced. See the Refrig-
erant Oil Capacities chart. When an A/C compressor is replaced, the refrigerant oil must be drained from the old

TUBE-A/C ORIFICE
DESCRIPTION
The fixed A/C orifice tube is installed in the A/C liquid
line and provides a restriction in the liquid refrigerant
line between the A/C condenser and the A/C evapora-
tor. This restriction established the pressure differential
between the high and low-pressure sides of the A/C
system.
The A/C orifice tube includes a diffuser screen (1),
O-ring seals (2) to seal it to the inner wall of the A/C
liquid line, an inlet filter screen (3) and the fixed orifice
(4).
OPERATION
The fixed A/C orifice tube is used to meter the flow of liquid refrigerant into the A/C evaporator. The high-pressure
liquid refrigerant from the A/C condenser expands into a low-pressure liquid as it passes through the metering orifice
and diffuser screen of the A/C orifice tube.
The A/C orifice tube is not serviceable and cannot be repaired and, if faulty or plugged, the A/C liquid line must be
replaced (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING/LINE-A/C LIQUID - DESCRIPTION).
DIAGNOSIS AND TESTING
A/C ORIFICE TUBE
WARNING: The A/C liquid line between the A/C condenser and the A/C orifice tube can become hot enough
to burn the skin. Use extreme caution when performing the following test toprevent possible personal
injury.
NOTE: The A/C orifice tube can be checked for proper operation using the following procedure. However,
the A/C orifice tube is only serviced as a part of the A/C liquid line. If the results of this test indicate that the
A/C orifice tube is obstructed or missing, the A/C liquid line must be replaced.
1. Confirm that the refrigerant system is properly charged (Refer to 24 - HEATING & AIR CONDITIONING - DIAG-
NOSIS AND TESTING - A/C PERFORMANCE).
2. Start the engine. Turn on the A/Csystem and confirm that the compressor clutch is engaged.
3. Allow the A/C system to operate for five minutes.
4. Lightly and cautiously touch the A/C liquid line near the condenser outlet at the front of the engine compartment.
TheA/Cliquidlineshouldbehottothetouch.
5. Touch the A/C liquid line near the evaporator inlet at the rear of the engine compartment. The A/C liquid line
should be cold to the touch.
6. If there is a distinct temperature differential between the two ends of the A/C liquid line, the A/C orifice tube is in
good condition. If there is little or no detectable temperature differential between the two ends of the A/C liquid
line, the A/C orifice tube is obstructed or missing and the A/C liquid line must be replaced (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING/LINE-A/C LIQUID - REMOVAL).

EMISSIONS CONTROL
DESCRIPTION
STATE DISPLAY TEST MODE
The switch inputs to the Powertrain Control Module (PCM) have two recognized states; HIGH and LOW. For this
reason, the PCM cannot recognize the difference between a selected switchposition versus an open circuit, a short
circuit, or a defective switch. If the State Display screen shows the changefromHIGHtoLOWorLOWtoHIGH,
assume the entire switch circuit to the PCM functions properly. Connect the DRB scan tool to the data link con-
nector and access the state display screen. Then access either State Display Inputs and Outputs or State Display
Sensors.
CIRCUIT ACTUATION TEST MODE
The Circuit Actuation Test Mode checks for proper operation of output circuits or devices the Powertrain Control
Module (PCM) may not internally recognize. The PCM attempts to activate these outputs and allow an observer to
verify proper operation. Most of the tests provide an audible or visual indication of device operation (click of relay
contacts, fuel spray, etc.). Except for intermittent conditions, if a device functions properly during testing, assume the
device, its associated wiring, and driver circuit work correctly. Connect the DRB scan tool to the data link connector
and access the Actuators screen.
DIAGNOSTIC TROUBLE CODES
A Diagnostic Trouble Code (DTC) indicates the PCM has recognized an abnormal condition in the system.
Remember that DTC’s are the results of a system or circuit failure, but do not directly identify the failed
component or components.
BULB CHECK
Each time the ignition key is turned to the ON position, the malfunction indicator (check engine) lamp on the instru-
ment panel should illuminate for approximately 2 seconds then go out. Thisis done for a bulb check.
OBTAINING DTC’S USING DRB SCAN TOOL
1. Obtain the applicable Powertrain Diagnostic Manual.
2. Obtain the DRB Scan Tool.
3. Connect the DRB Scan Tool to the data link (diagnostic) connector. This connector is located in the passenger
compartment at the lower edge of instrument panel, and near the steering column.
4. Turn the ignition switch on and access the “Read Fault” screen.
5. Record all the DTC’s and “freeze frame” information shown on the DRB scantool.
6. To erase DTC’s, use the “Erase Trouble Code” data screen on the DRB scan tool.Do not erase any DTC’s
until problems have been investigated and repairs have been performed.
TA S K M A N A G E R
The PCM is responsible for efficiently coordinating the operation of all the emissions-related components. The PCM
is also responsible for determining if the diagnostic systems are operating properly. The software designed to carry
out these responsibilities is called the ’Task Manager’.
MONITORED SYSTEMS
There are new electronic circuit monitors that check fuel, emission, engine and ignition performance. These moni-
tors use information from various sensor circuits to indicate the overalloperation of the fuel, engine, ignition and
emission systems and thus the emissions performance of the vehicle.
The fuel, engine, ignition and emission systems monitors do not indicate aspecific component problem. They do
indicate that there is an implied problem within one of the systems and thata specific problem must be diagnosed.
If any of these monitors detect a problem affecting vehicle emissions, theMalfunction Indicator Lamp (MIL) will be
illuminated. These monitors generate Diagnostic Trouble Codes that can be displayed with the MIL or a scan tool.

The following is a list of the system monitors:
Misfire Monitor
Fuel System Monitor
Oxygen Sensor Monitor
Oxygen Sensor Heater Monitor
Catalyst Monitor
Leak Detection Pump Monitor (if equipped)
All these system monitors require two consecutive trips with the malfunction present to set a fault.
Refer to the appropriate Powertrain Diagnostics Procedures manual for diagnostic procedures.
The following is an operation and description of each system monitor:
OXYGEN SENSOR (O2S) MONITOR
Effective control of exhaust emissions is achieved by an oxygen feedback system. The most important element of
the feedback system is the O2S. The O2S is located in the exhaust path. Once it reaches operating temperature
300° to 350°C (572° to 662°F), the sensor generates a voltage that is inversely proportional to the amount of oxy-
gen in the exhaust. The information obtained by the sensor is used to calculate the fuel injector pulse width. This
maintains a 14.7 to 1 Air Fuel (A/F) ratio. At this mixture ratio, the catalyst works best to remove hydrocarbons (HC),
carbon monoxide (CO) and nitrogen oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the Catalyst and Fuel Monitors.
The O2S can fail in any or all of the following manners:
slow response rate
reduced output voltage
dynamic shift
shortedoropencircuits
Response rate is the time required for the sensor to switch from lean to richonce it is exposed to a richer than
optimum A/F mixture or vice versa. As the sensor starts malfunctioning, itcould take longer to detect the changes
in the oxygen content of the exhaust gas.
The output voltage of the O2S ranges from 0 to 1 volt. A good sensor can easilygenerate any output voltage in this
range as it is exposed to different concentrations of oxygen. To detect a shift in the A/F mixture (lean or rich), the
output voltage has to change beyond a threshold value. A malfunctioning sensor could have difficulty changing
beyond the threshold value.
OXYGEN SENSOR HEATER MONITOR
If there is an oxygen sensor (O2S) shorted to voltage DTC, as well as a O2S heater DTC, the O2S fault MUST be
repaired first. Before checking the O2S fault, verify that the heater circuit is operating correctly.
Effective control of exhaust emissions is achieved by an oxygen feedback system. The most important element of
the feedback system is the O2S. The O2S is located in the exhaust path. Once it reaches operating temperature
300°C to 350°C (572°F to 662°F), the sensor generates a voltage that is inversely proportional to the amount of
oxygen in the exhaust. The information obtained by the sensor is used to calculate the fuel injector pulse width. This
maintains a 14.7 to 1 Air Fuel (A/F) ratio. At this mixture ratio, the catalyst works best to remove hydrocarbons (HC),
carbon monoxide (CO) and nitrogen oxide (NOx) from the exhaust.
The voltage readings taken from the O2S sensor are very temperature sensitive. The readings are not accurate
below 572°F (300°C). Heating of the O2S sensor is done to allow the engine controllertoshifttoclosedloopcontrol
as soon as possible. The heating element used to heat the O2S sensor must be testedtoensurethatitisheating
the sensor properly.
The O2S sensor circuit is monitored for a drop in voltage. The sensor outputis used to test the heater by isolating
the effect of the heater element on the O2S sensor output voltage from the other effects.
LEAK DETECTION PUMP MONITOR (IF EQUIPPED)
The leak detection assembly incorporates two primary functions: it must detect a leak in the evaporative system and
seal the evaporative system so the leak detection test can be run.

The primary components within the assembly are: A three port solenoid thatactivates both of the functions listed
above; a pump which contains a switch, two check valves and a spring/diaphragm, a canister vent valve (CVV) seal
which contains a spring loaded vent seal valve.
Immediately after a cold start, between predetermined temperature thresholds limits, the three port solenoid is briefly
energized. This initializes the pump by drawing air into the pump cavity and also closes the vent seal. During non
test conditions the vent seal is held open by the pump diaphragm assembly which pushes it open at the full travel
position. The vent seal will remain closed while the pump is cycling due to the reed switch triggering of the three
port solenoid that prevents the diaphragm assembly from reaching full travel. After the brief initialization period, the
solenoid is de-energized allowing atmospheric pressure to enter the pumpcavity, thus permitting the spring to drive
the diaphragm which forces air out of the pump cavity and into the vent system. When the solenoid is energized
and de energized, the cycle is repeated creating flow in typical diaphragmpump fashion. The pump is controlled in
2 modes:
Pump Mode: The pump is cycled at a fixed rate to achieve a rapid pressure build in order to shorten the overall test
length.
Test Mode: The solenoid is energized with a fixed duration pulse. Subsequent fixed pulses occur when the dia-
phragm reaches the Switch closure point.
The spring in the pump is set so that the system will achieve an equalized pressure of about 7.5” H20. The cycle
rate of pump strokes is quite rapid as the system begins to pump up to this pressure. As the pressure increases, the
cycle rate starts to drop off. If there is no leak in the system, the pump would eventually stop pumping at the equal-
ized pressure. If there is a leak, it will continue to pump at a rate representative of the flow characteristic of the size
of the leak. From this information we can determine if the leak is larger than the required detection limit (currently
set at .040” orifice by CARB). If a leak is revealed during the leak test portion of the test, the test is terminated at
the end of the test mode and no further system checks will be performed.
After passing the leak detection phase of the test, system pressure is maintained by turning on the LDP’s solenoid
until the purge system is activated. Purge activation in effect creates a leak. The cycle rate is again interrogated and
when it increases due to the flow through the purge system, the leak check portion of the diagnostic is complete.
The canister vent valve will unseal the system after completion of the testsequence as the pump diaphragm assem-
bly moves to the full travel position.
Evaporative system functionality will be verified by using the stricter evap purge flow monitor. At an appropriate
warm idle the LDP will be energized to seal the canister vent. The purge flowwill be clocked up from some small
value in an attempt to see a shift in the02 control system. If fuel vapor, indicated by a shift in the 02 control, is
present the test is passed. If not, it is assumed that the purge system is notfunctioning in some respect. The LDP
is again turned off and the test is ended.
MISFIRE MONITOR
Excessive engine misfire results in increased catalyst temperature and causes an increase in HC emissions. Severe
misfires could cause catalyst damage. To prevent catalytic convertor damage, the PCM monitors engine misfire.
The Powertrain Control Module (PCM) monitors for misfire during most engine operating conditions (positive torque)
by looking at changes in the crankshaft speed. If a misfire occurs the speedof the crankshaft will vary more than
normal.
FUEL SYSTEM MONITOR
To comply with clean air regulations, vehicles are equipped with catalytic converters. These converters reduce the
emission of hydrocarbons, oxides of nitrogen and carbon monoxide. The catalyst works best when the Air Fuel (A/F)
ratio is at or near the optimum of 14.7 to 1.
The PCM is programmed to maintain the optimum air/fuel ratio of 14.7 to 1. This is done by making short term
corrections in the fuel injector pulse width based on the O2S sensor output. The programmed memory acts as a self
calibration tool that the engine controller uses to compensate for variations in engine specifications, sensor toler-
ances and engine fatigue over the life span of the engine. By monitoring theactual fuel-air ratio with the O2S sen-
sor (short term) and multiplying that with the program long-term (adaptive) memory and comparing that to the limit,
it can be determined whether it will pass an emissions test. If a malfunction occurs such that the PCM cannot main-
tain the optimum A/F ratio, then the MIL will be illuminated.