Dodge RAM 1500 1998 Owner's Manual page 324

DR
COOLING (Continued)
CONDITION
TEMPERATURE GAUGE READING
INCONSISTENT (ERRATIC,
CYCLES OR FLUCTUATES)
NOTE: Information on daash cluster
is displayed based on broadcast
data from ECM. DTC will be set for
engine sensore circuit wiring.
RADIATOR CAP LEAKING STEAM
AND /OR COOLANT INTO
RESERVOIR BOTTLE.
(TEMPERATURE GAUGE MAY
READ HIGH)
HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING.
NOISY FAN
POSSIBLE CAUSES
1. Heavy duty cooling system,
extreme cold ambient (outside)
temperature or heater blower motor
in high position.
2. Temperature gauge or sensor
defective.
3. Temporary heavy usage or load.
4. Air trapped in cooling system.
5. Water pump
6. Air leak on suction side of water
pump.
1. Radiator cap defective.
2. Radiator neck surface damaged.
1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
reservoir/overflow system.
1. Fan blade(s) loose, damaged.
2. Electronically controlled viscous
fan drive.
3. Fan blades striking surrounding
objects.
4. Electronically controlled viscous
fan drive bearing concern.
5. Electronically controlled viscous
fan stuck on.
6. Obstructed air flow through
radiator.
COOLING
CORRECTION
1. None. System operating normally.
2. Check cluster or engine coolant
temp sensor (Refer to 8 -
ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND
TESTING)
3. None. Normal condition.
4. Fill cooling system (Refer to 7 -
COOLING - STANDARD
PROCEDURE).
5. Replace water pump.
6. Check for leak. (Refer to 7 -
COOLING - DIAGNOSIS AND
TESTING)
1. Replace radiator cap.
2. Replace radiator.
1. Replace radiator cap, check vent
hose between radiator and reservoir
bottle for blockage also check
reservoir bottle vent for blockage.
1. Replace fan blade assembly.
2. None. Normal condition.
3. Locate contact point and repair
as necessary.
4. Check viscous fan drive (Refer to
7 - COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
5. Check viscous fan drive(Refer to
7 - COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
6. Remove obstruction.
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