1998 DODGE RAM 1500 Symptoms

²Ohmmeter - Used to check the resistance
between two points of a circuit. Low or no resistance
in a circuit means good continuity.
CAUTION: Most of the electrical components used
in today's vehicles are Solid State. When checking
resistance in these circuits use a meter with a 10 -
megohm or greater impedance rating. In addition,
make sure the power is disconnected from the cir-
cuit. Circuits that are powered up by the vehicle's
electrical system can cause damage to the equip-
ment and provide false readings.
²Probing Tools - These tools are used for probing
terminals in connectors (Fig. 5). Select the proper
size tool from Special Tool Package 6807, and insert
it into the terminal being tested. Use the other end
of the tool to insert the meter probe.
INTERMITTENT AND POOR CONNECTIONS
Most intermittent electrical problems are caused
by faulty electrical connections or wiring. It is also
possible for a sticking component or relay to cause a
problem. Before condemning a component or wiring
assembly, check the following items.
²Connectors are fully seated
²Spread terminals, or terminal push out
²
Terminals in the wiring assembly are fully seated
into the connector/component and locked into position
²Dirt or corrosion on the terminals. Any amount
of corrosion or dirt could cause an intermittent prob-
lem
²Damaged connector/component casing exposing
the item to dirt or moisture
²Wire insulation that has rubbed through causing
a short to ground
²Some or all of the wiring strands broken inside
of the insulation
²Wiring broken inside of the insulation
TROUBLESHOOTING WIRING PROBLEMS
When troubleshooting wiring problems there are
six steps which can aid in the procedure. The steps
are listed and explained below. Always check for non-factory items added to the vehicle before doing any
diagnosis. If the vehicle is equipped with these items,
disconnect them to verify these add-on items are not
the cause of the problem.
(1) Verify the problem.
(2) Verify any related symptoms. Do this by per-
forming operational checks on components that are
in the same circuit. Refer to the wiring diagrams.
(3) Analyze the symptoms. Use the wiring dia-
grams to determine what the circuit is doing, where
the problem most likely is occurring and where the
diagnosis will continue.
(4) Isolate the problem area.
(5) Repair the problem area.
(6) Verify the proper operation. For this step,
check for proper operation of all items on the
repaired circuit. Refer to the wiring diagrams.
STANDARD PROCEDURE
STANDARD PROCEDURE - ELECTROSTATIC
DISCHARGE (ESD) SENSITIVE DEVICES
All ESD sensitive components are solid state and a
symbol (Fig. 6) is used to indicate this. When han-
dling any component with this symbol, comply with
the following procedures to reduce the possibility of
electrostatic charge build up on the body and inad-
vertent discharge into the component. If it is not
known whether the part is ESD sensitive, assume
that it is.
(1) Always touch a known good ground before han-
dling the part. This should be repeated while han-
dling the part and more frequently after sliding
across a seat, sitting down from a standing position,
or walking a distance.
(2) Avoid touching electrical terminals of the part,
unless instructed to do so by a written procedure.
(3) When using a voltmeter, be sure to connect the
ground lead first.
(4) Do not remove the part form it's protective
packing until it is time to install the part.
(5) Before removing the part from it's pakage,
ground the pakage to a known good ground on the
vehicle.
Fig. 5 PROBING TOOL
1 - SPECIAL TOOL 6801
2 - PROBING END
Fig. 6 ELECTROSTATIC DISCHARGE SYMBOL
8W - 01 - 8 8W-01 WIRING DIAGRAM INFORMATIONDR
WIRING DIAGRAM INFORMATION (Continued)

DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS
WARNING: R-134a SERVICE EQUIPMENT OR VEHI-
CLE A/C SYSTEM SHOULD NOT BE PRESSURE
TESTED OR LEAK TESTED WITH COMPRESSED
AIR. MIXTURE OF AIR and R-134a CAN BE COM-
BUSTIBLE AT ELEVATED PRESSURES. THESE MIX-
TURES ARE POTENTIALLY DANGEROUS AND MAY
RESULT IN FIRE OR EXPLOSION CAUSING INJURY
OR PROPERTY DAMAGE.
AVOID BREATHING A/C REFRIGERANT AND LUBRI-
CANT VAPOR OR MIST. EXPOSURE MAY IRRITATE
EYES, NOSE AND THROAT. USE ONLY APPROVED
SERVICE EQUIPMENT MEETING SAE REQUIRE-
MENTS TO DISCHARGE R-134a SYSTEM. IF ACCI-
DENTAL SYSTEM DISCHARGE OCCURS,
VENTILATE WORK AREA BEFORE RESUMING SER-
VICE.
NOTE: The refrigerant system does come from the
factory with a yellow tracer dye already installed to
aid in detection of leaks.
If the A/C system is not cooling properly, determine
if the refrigerant system is fully charged with
R-134a. This is accomplished by performing a system
Charge Level-Check or Fill. If while performing this
test A/C liquid line pressure is less than 345 kPa (50
psi) proceed to System Empty procedure. If liquid
line pressure is greater than 345 kPa (50 psi) proceed
to System Low procedure. If the refrigerant system is
empty or low in refrigerant charge, a leak at any line
fitting or component seal is likely. A review of the fit-
tings, lines and components for oily residue is an
indication of the leak location. To detect a leak in the
refrigerant system, perform one of the following pro-
cedures as indicated by the symptoms.
SYSTEM EMPTY
(1) Evacuate the refrigerant system to the lowest
degree of vacuum possible (approx. 28 in Hg.). Deter-
mine if the system holds a vacuum for 15 minutes. If
vacuum is held, a leak is probably not present. If sys-
tem will not maintain vacuum level, proceed with
this procedure.(2) Prepare a 0.284 Kg. (10 oz.) refrigerant charge
to be injected into the system.
(3) Connect and dispense 0.284 Kg. (10 oz.) of
refrigerant into the evacuated refrigerant system.
(4) Proceed to Step 2 of System Low procedure.
SYSTEM LOW
(1) Determine if there is any (R-134a) refrigerant
in the system.
(2) Position the vehicle in a wind free work area.
This will aid in detecting small leaks.
(3) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run for five minutes with the system
set to the following:
²Transmission in Park or Neutral with parking
brake set
²Engine idling at 700 rpm
²A/C controls set in 100 percent outside air
²Blower switch in the high A/C position
²A/C in the ON position
²Open all windows
CAUTION: A leak detector designed for R-12 refrig-
erant (only) will not detect leaks in a R-134a refrig-
erant system.
(4) Shut off the vehicle and wait 2 to 7 minutes.
Then use an Electronic Leak Detector that is
designed to detect R-134a type refrigerant and search
for leaks. Fittings, lines, or components that appear
to be oily usually indicates a refrigerant leak. To
inspect the evaporator core for leaks, insert the leak
detector probe into the drain tube opening or a heat
duct. A R-134a dye is available to aid in leak detec-
tion, use only DaimlerChrysler approved refrigerant
dye.
24 - 44 PLUMBINGDR
PLUMBING (Continued)