Jeep Cherokee 2000 Service Manual - Lamp Diagnosis
LAMP DIAGNOSIS
TABLE OF CONTENTS
page
page
DIAGNOSIS AND TESTING
DIAGNOSTIC PROCEDURES . . . . . . . . . . . . . . . . 3
SYSTEM DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . 3
DIAGNOSIS AND TESTING
DIAGNOSTIC PROCEDURES
When a vehicle experiences problems with the
headlamp system, verify the condition of the battery
connections, fuses, charging system, headlamp bulbs,
wire connectors, relay, high beam switch, dimmer
switch, and headlamp switch. Refer to Group 8W,
Wiring Diagrams for component locations and circuit
information.
SYSTEM DIAGNOSIS
HEADLAMP
Always begin any diagnosis by testing all of the
fuses and circuit breakers in the system. Refer to
Group 8W, Wiring Diagrams.
Conventional and halogen headlamps are inter-
changeable. It is recommended that they not be
intermixed on a given vehicle.
CONDITION
POSSIBLE CAUSES
CORRECTION
HEADLAMPS ARE DIM
WITH ENGINE IDLING
1. Loose or corroded battery cables.
1. Clean and secure battery cable clamps
and posts.
OR IGNITION TURNED
OFF
2. Loose or worn generator drive
belt.
2. Adjust or replace generator drive belt.
3. Charging system output too low.
3. Test and repair charging system, refer to
Group 8A,
4. Battery has insufficient charge.
4. Test battery state-of-charge,
refer to Group 8A.
5. Battery is sulfated or shorted.
5. Load test battery, refer to Group 8A.
6. Poor lighting circuit Z1-ground.
6. Test for voltage drop across Z1-ground
locations, refer to Group 8W.
7. Both headlamp bulbs defective.
7. Replace both headlamp bulbs.
HEADLAMP BULBS BURN
OUT
1. Charging system output too high.
1. Test and repair charging system, refer to
Group 8A.
FREQUENTLY
2. Loose or corroded terminals or
splices in circuit.
2. Inspect and repair all connectors and
splices, refer to Group 8W.
HEADLAMPS ARE DIM
WITH ENGINE RUNNING
1. Charging system output too low.
1. Test and repair charging system, refer to
Group 8A.
ABOVE IDLE*
2. Poor lighting circuit Z1-ground.
2. Test for voltage drop across Z1-ground
locations, refer to Group 8W.
3. High resistance in headlamp
circuit.
3. Test amperage draw of headlamp circuit.
4. Both headlamp bulbs defective.
4. Replace both headlamp bulbs.
XJ
LAMPS
8L - 3