CONDITION
POSSIBLE CAUSES
CORRECTION
COOLANT LOSS TO THE
GROUND WITHOUT
PRESSURE CAP BLOWOFF.
GAUGE IS READING HIGH
OR HOT
1. Coolant leaks in radiator, cooling
system hoses, water pump or engine.
1. Pressure test and repair as
necessary. Refer to Testing Cooling
System For Leaks in this group.
HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING
1. Vacuum created in cooling system on
engine cool-down is not being relieved
through pressure/vent cap.
1. Cap relief valve stuck. Refer to
Pressure/Vent Cap in this group.
Replace if necessary.
NOISY FAN
1. Fan blades loose.
1. Replace fan blade assembly.
Refer to Cooling Sytem Fans in this
group.
2. Fan blades striking a surrounding
object.
2. Locate point of fan blade contact
and repair as necessary.
3. Air obstructions at radiator or air
conditioning condenser.
3. Remove obstructions and/or
clean debris or insects from radiator
or A/C condenser.
4. Thermal viscous fan drive has
defective bearing.
4. Replace fan drive. Bearing is not
serviceable. Refer to Viscous Fan
Drive in this group.
5. A certain amount of fan noise (roaring)
may be evident on models equipped with
a thermal viscous fan drive. Some of this
noise is normal.
5. Refer to Viscous Fan Drive in
this group for an explanation of
normal fan noise.
INADEQUATE AIR
CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)
1. Radiator and/or A/C condenser is
restricted, obstructed or dirty (insects,
leaves etc.).
1. Remove restriction and/or clean
as necessary. Refer to Radiator
Cleaning in this group.
2. Thermal viscous fan drive is
freewheeling.
2. Refer to Viscous Fan Drive for
diagnosis. Repair as necessary.
3. Engine is overheating (heat may be
transferred from radiator to A/C
condenser. High underhood temperatures
due to engine overheating may also
transfer heat to A/C components).
3. Correct overheating condition.
Refer to text in Group 7, Cooling.
4. The cooling system is equipped with
air seals at the radiator and/or A/C
condenser. If these seals are missing or
damaged, not enough air flow will be
pulled through the radiator and A/C
condenser.
4. Check for missing or damaged
air seals and repair as necessary.
7 - 12
COOLING SYSTEM
XJ
DIAGNOSIS AND TESTING (Continued)
2000 JEEP CHEROKEE