1999 DODGE RAM hood open

Use only NEW, moisture-free refrigerant oil in A/C systems.
Refrigerant oil is highly refined with a very low moisture content.
Oil container must be tightly closed when not in use, or moisture from
air will be absorbed into refrigerant oil.
Refrigerant R-134a systems use Polyalkylene Glycol (PAG)
refrigerant oil. Using a mineral oil based lubricant with R-134a
systems will result in A/C compressor failure due to lack of proper
lubrication.
All compressors have different lubrication requirements and
use different Polyalkylene Glycol (PAG) refrigerant oils. Use only the\
specified PAG refrigerant oil for the appropriate system and A/C
compressor. Always check the underhood A/C specification label or A/C
compressor label before adding refrigerant oil to A/C
compressor/system. See listing of refrigerant oils currently available
from the vehicle manufacturers.
NOTE: PAG oil absorbs moisture very rapidly, 2.3-5.6 percent by
weight as compared to a mineral oil absorption rate of .005
percent by weight.
CHRYSLER CORP., JEEP & EAGLE
Use ND-8 PAG oil, SUN PAG 56 oil, SP-10 PAG oil, or SP-20 PAG
oil.
FORD MOTOR CO.
Use YN-12B or YN-12C PAG Refrigerant Oil (specification WSH-
M1C231-B) or SP-20 PAG Oil (specification WST-M1C231-B2).
GENERAL MOTORS
On all models except Saturn, use PAG Refrigerant Oil (Part
No. 12345923). On Saturn, use Saturn PAG refrigerant oil.
SERVICING PRECAUTIONS
DISCHARGING SYSTEM
Discharge A/C system, using approved refrigerant
recovery/recycling equipment before loosening any fittings. Follow
refrigerant recovery/recycling equipment manufacturer's instructions.
DISCONNECTING LINES & FITTINGS
After system is discharged, carefully clean area around all
fittings to be opened. Always use 2 wrenches when loosening or
tightening fittings. Some refrigerant lines are connected with a
spring-lock coupling. Special tools may be required to disconnect
lines. To prevent dirt and moisture from entering system, cap all
openings as soon as lines are removed. DO NOT remove service valve
caps until ready to connect lines and fittings.
NOTE: All R-134a based systems use 1/2-16 ACME threaded fittings.
Ensure all replacement parts match the connections of the
system being worked on.
CONNECTING LINES & FITTINGS
Always use new a gasket or "O" rings when connecting lines or

Fig. 2: Identifying Compressor Clutch Relay Terminals (Typical)
Courtesy of Chrysler Corp.
BLOWER MOTOR RESISTOR
1) Disconnect negative battery cable. Disconnect blower motor
resistor harness connector. Using an ohmmeter, check for continuity
between all 4 front blower motor resistor terminals, or 3 rear blower
motor resistor terminals. If continuity exists, go to next step. If
continuity does not exist, replace faulty blower motor resistor.
2) Check for open or short in circuits between blower motor
resistor and A/C-heater control panel. Also check for open or short in
wire between blower motor resistor and blower motor.
BLOWER MOTOR SWITCH
Front
1) Using a voltmeter, check underhood power distribution
center for battery voltage at fuse No. 5 (40-amp) on Dakota and
Durango, or fuse No. 5 (40-amp) on Ram Pickup. If battery voltage
exists, go to next step. If battery voltage does not exist, check for
open in Red wire between battery and underhood power distribution
center. If Red wire is okay, replace underhood power distribution
center.
2) Disconnect negative battery cable. Remove A/C-heater
control panel. See A/C-HEATER CONTROL PANEL R & I . Disconnect A/C-
heater control panel harness connector. Using an ohmmeter, check for
continuity between A/C-heater control panel harness connector terminal
No. 7 (Black wire on Dakota and Durango; Black/Orange on Ram Pickup)
and ground. If continuity exists, go to step 4).
3) If continuity does not exist, repair open in Black or
Black/Orange wire between A/C-heater control panel harness connector
terminal No. 7 and ground connector located at lower right corner of
instrument panel (Dakota and Durango) or behind center of instrument
panel (Ram Pickup).
4) Place mode control knob to any position except OFF. Using
an ohmmeter, check for continuity between A/C-heater control panel
connector terminal No. 7 and terminals No. 3, 4, 5, and 6 while
rotating blower motor switch. See Fig. 3.
5) If continuity does not exist at any terminal, replace
faulty A/C-heater control panel. If continuity exists as specified,
check for open in circuits between A/C-heater control panel and blower
motor resistor. Also check for an open in circuit between A/C-heater

from housing. To install, reverse removal procedure. Install new "O"
rings to A/C fittings. Evacuate and charge A/C system.
Removal & Installation (Durango - Rear Evaporator Core)
1) Disconnect negative battery cable. Discharge A/C system,
using approved refrigerant recovery/recycling equipment. Remove
headliner from passenger compartment of vehicle. Remove sun visors and
sun visor arm supports.
2) Remove coat hooks, overhead assist handle and dome light.
If equipped, remove overhead console. Remove air outlet bezel from
rear A/C-heater assembly. Remove rear blower motor switch. Remove
upper liftgate opening trim. Disengage "A", "B", "C", and "D" pillar
trim as necessary to prevent trim panel interference.
3) Move second and third row seats to cargo position. Move
front seats to full recline position. Remove headliner fasteners.
Carefully bow headliner and remove through lift gate opening.
4) Disconnect "B" pillar drain hoses from "Y" fittings.
Disconnect "B" pillar refrigerant lines and plug or cover all openings
in A/C system. Remove lower A/C-heater assembly cover. Remove screws
securing refrigerant tube and retaining strap to right side of upper
housing cover. Remove evaporator core. To install, reverse removal
procedure. Install new "O" rings to A/C fittings. Evacuate and charge
A/C system.
Removal & Installation (Ram Pickup - Front)
1) Remove and disassemble A/C-heater housing. See
A/C-HEATER ASSEMBLY . Separate halves of A/C-heater housing and remove
top half. Remove evaporator or heater core from housing.
2) To install, reverse removal procedure. Install new "O"
rings to A/C fittings. Evacuate and charge A/C system. Fill cooling
system. On 5.9L diesel engine, engine is equipped with a one-way check
valve. DO NOT run engine while filling cooling system. Fill engine
with engine turned off.
INSTRUMENT PANEL
Removal & Installation (Dakota & Durango)
1) Disconnect negative battery cable. Disable air bag system.
See AIR BAG SYSTEM SAFETY article. Place front wheels in straight-
ahead position. Remove sill trim from both doorways. Remove kick panel
covers from both sides of vehicle. Remove mounting screws for hood
release handle.
2) Remove steering column trim panel and support bracket.
Remove tilt steering column lever (if equipped). Remove upper and
lower shrouds from steering column. Unplug driver's side air bag
module. Loosen multifunction switch wiring harness connector screw and
disconnect from switch. Screw will remain in connector.
3) Disconnect PRNDL cable. Disconnect shift cable from
steering column. Remove steering coupler lock pin. Remove toe plate
retaining screws. Remove steering column mounting bolts and remove
steering column from vehicle.
4) Remove screw from bulkhead wiring harness connector and
disconnect. Disconnect 2 body wiring harness connectors located next
to bulkhead connector. Disconnect 3 wiring harness connectors, from
junction block, located nearest to dash panel. Disconnect brake light
switch connector. Disconnect Rear Wheel Anti-Lock (RWAL) brake module
(if equipped), located near steering column support brackets.
5) Disconnect plastic retainer clip from parking brake
linkage rod, located at back of parking brake release handle. Remove
rod end from parking brake handle. Remove instrument panel center
support bracket. Unplug vacuum harness connector located at left end
of A/C-heater housing. Disconnect Air Bag Control Module (ACM)
connector.

6) Remove glove box. Reach through glove box opening and
disconnect antenna coaxial cable connector. Disconnect blower motor
connector located above glove box opening, near support brace for A/C-
heater housing. Disconnect radio ground strap. Loosen instrument panel
roll down bracket bolts about 2 turns, located at lower corners on
both sides of instrument panel. Remove 5 screws across top of dash
panel at base of windshield, removing center screw last.
7) Roll down instrument panel and install a temporary support
hook that is about 18" (457 mm) in length. Install hook from center
hole in instrument panel to center hole of dash panel. Pull lower
instrument panel outward until both roll down bracket bolts are in
slotted roll down position. Instrument panel should now be supported
and away from firewall.
8) Disconnect 2 door harness connectors, located on a bracket
near right end of instrument panel. Disconnect blower motor resistor.
Disconnect temperature control cable from A/C-heater housing and
remove from housing. See Fig. 5. Disconnect demister duct flexible
hose from A/C-heater housing.
9) Ensure instrument panel is free and clear for removal.
With the aid of an assistant, remove temporary support hook. Lift
instrument panel off of roll down bracket bolts and remove from
vehicle.
10) To install, reverse removal procedure. Ensure all wiring
and hoses are clear and not pinched. Tighten bolts and nuts to
specification. See TORQUE SPECIFICATIONS . Enable air bag system. See
AIR BAG SYSTEM SAFETY article.
Removal & Installation (Ram Pickup)
1) Disable air bag system. See AIR BAG SYSTEM SAFETY article.
Disconnect negative battery cable. Drain cooling system. Remove left
and right kick panel trim. Remove 5 screws and knee bolster/steering
column cover. Remove hood release and parking brake release handle
screws from lower instrument panel support. Remove 6 screws and
instrument panel support. Disconnect air bag connector at lower left
corner of instrument panel.
2) Pull PRNDL cable and twist to remove from position arm.
Push tab on bottom of cable retainer upward, then squeeze sides to
remove retainer from column. Remove tilt lever (tilt column only).
Remove both upper and lower shrouds from column. Remove lower fixed
column shroud. Loosen multifunction switch connector screw. Screw will
remain in connector.
3) Remove remaining steering column electrical connectors.
Remove air bag wiring harness from steering column wiring trough.
Remove wiring trough from steering column. Remove 3 toe plate nuts and
washers.
4) Remove 2 nuts and washers attaching steering column
bracket to instrument panel steering column support bracket. Allow
column to lower and rest on seat. Remove 2 screws from bottom of Air
Bag Control Module (ACM) cover. Remove 4 screws holding ACM to
transmission tunnel.
5) Disconnect wiring at ACM. Disconnect instrument panel left
side wiring connectors. Remove screw holding brake release to bottom
of instrument panel. Disconnect instrument panel right side wiring
connectors, which includes 2 connectors attached to A/C-heater
assembly housing, courtesy light connector, antenna cable and 2 body
connectors. Disconnect vacuum harness from A/C-heater system.
6) Remove 5 screws holding instrument panel to dash. Loosen
lower instrument panel pivot bolts. Roll instrument panel downward.
Remove instrument panel from vehicle.
7) To install, reverse removal procedure. Ensure all wiring
and hoses are clear and not pinched. Tighten bolts and nuts to
specification. See TORQUE SPECIFICATIONS . Enable air bag system. See
AIR BAG SYSTEM SAFETY article.

Refrigerant R-12 based systems use mineral oil, while R-134a
systems use synthetic Polyalkylene Glycol (PAG) oils. Using a mineral
oil based lubricant with R-134a will result in A/C compressor failure
due to lack of proper lubrication.
Following are the most common R-134a refrigerant oils used by
most domestic vehicles:
Chrysler Corp., Eagle & Jeep
Use ND-8 PAG oil, SUN PAG 56 oil, SP-10 PAG Oil, or SP-20 PAG
oil.
Ford Motor Co.
Use YN-12B or YN-12C PAG Refrigerant Oil (specification WSH-
M1C231-B) or SP-20 PAG Oil (specification WST-M1C231-B2).
General Motors
On all models except Saturn, use PAG Refrigerant Oil (Part
No. 12345923). On Saturn, use Saturn PAG refrigerant oil.
NOTE: PAG oil absorbs moisture very rapidly, 2.3-5.6 percent by
weight as compared to a mineral oil absorption rate of .005
percent by weight.
NOTE: Use ONLY the specified oil for the appropriate system or A/C
compressor. Always check the underhood A/C specification
label or A/C compressor label before adding refrigerant oil
to A/C system.
SYSTEM SERVICE VALVES
SCHRADER-TYPE VALVES
NOTE: Although similar in construction and operation to a tire
valve, NEVER replace a Schrader-type valve with a tire
valve.
Schrader valve is similar in construction and operation to a
tire valve. See Fig. 4. When a test gauge hose is attached (hose has
built-in valve core depressor), Schrader stem is pushed inward to the
open position and allows system pressure to reach the gauge.
If test hose being used does not have a built-in core
depressor, an adapter must be used. Never attach hoses or adapters to
a Schrader valve unless it is first connected to manifold gauge set.
Fig. 4: Schrader Service Valve (Compressor Location Shown)
SPECIAL VALVE CONNECTORS
On some General Motors models, thread size on high-side

Fig. 24: Electronic Leak Detector
PREPARATION FOR LEAK TESTING
Connect manifold gauge set to air conditioning system. Ensure
low-side and high-side gauge set valves are closed. Check system
pressure. It should be at least 50 psi (3.5 kg/cm
). If system is
empty, evacuate A/C system and apply 28 in. Hg of vacuum. If system
holds vacuum for 15 minutes there most likely are no leaks present. If
low, add just enough refrigerant (about 10 ounces) to bring system to
50 psi (3.5 kg/cm
).
Ensure all joints, connections, and fittings are free of oil
dirt and other contaminants. Using a refrigerant leak detector, check
all refrigerant line connections for leaks. Check condenser and
compressor seal area.
Start engine and allow to idle. Operate A/C system for about
5 minutes. Set A/C controls to outside air, and high blower speed.
Turn A/C on, and open vehicle windows. Turn engine off and wait 2-7
minutes. Refrigerant is heavier than air. Always check for leaks at
bottom of refrigerant lines and components. Refrigerant oil will leak
with refrigerant. Visually check all connections and compressor clutch
area for oil stains. If compressor shaft seal is leaking, a fresh oil
streak will normally be seen on underside of hood, above compressor
clutch.
Always perform leak testing after A/C service. Move
refrigerant leak detector slowly to check for leaks, as leaks will not


AN TI- T H EFT S YSTE M

1999 D odge P ic ku p R 1500
1999 ACCESSORIES & EQUIPMENT
CHRY - Anti-Theft Systems
Ram Pickup, Ram Van & Ram Wagon
DESCRIPTION
The Vehicle Theft Security System (VTSS) provides an engine
no-run feature, flashes headlights and sounds horn if any door or hood
is opened without using key or remote keyless entry transmitter, or if
battery cables are disconnected then reconnected when system is
activated.
Anti-theft system is controlled by Central Timer Module
(CTM). CTM is located under driver's side of dash panel, right of
steering column. If CTM is faulty, CTM cannot be repaired and must be
replaced.
VTSS is also equipped with a power-up mode. If battery is
disconnected or looses power while VTSS is armed, VTSS system remains
armed when power is restored. A temper alert signal is sounded on
vehicle entry if VTSS was triggered while away from vehicle. Horn will
sound 3 times alerting owner VTSS was triggered.
OPERATION
ARMING PROCEDURE (PASSIVE)
Remove key from ignition. Ensure headlights are off. Lock
doors while open, using power lock switch. Power lock switch will not
operate with key in ignition or headlights on while door is open.
Vehicle Theft Security System (VTSS) will not arm using key in lock
cylinder or mechanical lock button. While system is arming, SECURITY
light will flash rapidly for 15 seconds. Opening any door or turning
the ignition key while light is flashing will abort arming process.
Once arming process is complete, SECURITY light will go out.
ARMING PROCEDURE (ACTIVE)
Pressing Remote Keyless Entry (RKE) transmitter LOCK button
will actively arm Vehicle Theft Security System (VTSS). All doors must\
be closed and ignition switch in OFF position. While system is arming,
SECURITY light will flash rapidly for 15 seconds. Opening any door or
turning the ignition key while light is flashing will abort arming
process. Once arming process is complete, SECURITY light will go out.
DISARMING
Vehicle Theft Security System (VTSS) can be disarmed 2 ways:
unlock vehicle using key in any door and pressing remote keyless entry
transmitter UNLOCK button. If alarm has been set off, either method
can be used to disarm and shut-off horn.
CENTRAL TIMER MODULE (CTM)
Central Timer Module (CTM) is Vehicle Theft Security System
(VTSS) processor. CTM uses the data bus network to allow sharing and
reporting of sensor information. If a door ajar sensor is opened while
VTSS is set, a signal is sent to flash headlights and sound horn. PCM
is also notified through bus network to enable engine no-run feature.

TROUBLE SHOOTING
NOTE: To trouble shoot mechanical engine components, see
appropriate table in TROUBLE SHOOTING article in GENERAL
INFORMATION.
REMOVAL & INSTALLATION
CAUTION: When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may exist
until computer systems have completed a relearn cycle. See
COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION
before disconnecting battery.
NOTE: For installation reference, label all electrical connectors,
vacuum hoses and fuel lines before removal. Also place mating
marks on engine hood and other major assemblies before
removal.
FUEL PRESSURE RELEASE
CAUTION: Fuel system is under pressure. Pressure must be released
before servicing fuel system components.
Gasoline
1) Disconnect negative battery cable. Loosen fuel tank cap to
release tank pressure. Press on filler tube flap to relieve any
additional tank pressure.
NOTE: Fuel filler tube has spring-loaded flap located below fuel
fill cap to serve as secondary seal if fuel fill cap is not
tightened. It is part of EVAP monitor system when vehicle is
equipped with leak detection pump (LDP). Vehicle may be
equipped with flap installed into fuel filler tube even if
vehicle is NOT equipped with LDP and EVAP monitor system.
2) Remove fuel pump relay from Power Distribution Center
(PDC). For location of relay, refer to label on underside of PDC
cover. Start and run engine until it stalls. Attempt restarting engine
until it will no longer run.
3) Unplug connector from an injector. Attach one end of a
jumper wire (18 gauge or smaller) with alligator clips to either
injector terminal. Connect other end of jumper wire to positive side
of battery. Connect one end of a second jumper wire to remaining
injector terminal.
WARNING: Powering an injector for more than a few seconds will
permanently damage injector.
4) Touch other end of second jumper wire to negative terminal
of battery for no more than a few seconds. Place a rag below fuel
line. Disconnect quick-connect fitting at fuel rail. See FUEL LINE
DISCONNECT FITTINGS. Return fuel pump relay to PDC.
Compressed Natural Gas Fuel Tube Purging (5.2L)
1) Close control valve (clockwise) on all fuel cylinders.
Open manual shutoff valve (open when handle is parallel to fuel
tubes).
2) Start and operate engine until it runs out of fuel.
Attempt 3 more engine starts. If check valve or fuel fill receptacle