Cherokee 2WD L6-4.0L VIN S (1998)
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Loss of Ignition Run Only
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Passenger Squib Circuit Shorted
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Loss of Ignition Run/Start
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Either Squib Term Shorted to Battery
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Either Squib Term Shorted to Ground
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No Cluster CCD Bus Message
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No CCD Communication *
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Passenger Squib Circuit Open
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Warning Lamp Circuit Open/Shorted
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Pressure Switch Circuit Open/Shorted
*1997 Model Year
Compass/Mini-Trip Computer
The Compass/Mini-Trip Computer (CMTC) is in the overhead console. It displays the following information:
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Compass direction
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Average Fuel Economy (ECO)
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Current outside temperature
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Instantaneous Fuel Economy (ECO)
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Elapsed Time (ET)
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Trip Odometer (ODO)
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Distance To Empty (DTE)
All of the information required by the CMTC except the ambient temperature and compass direction is transmitted over the CCD bus.
The CMTC can perform an independent self-test. This can be accomplished by using either the DRB or pressing both US/M and STEP buttons and then
turning the ignition key on. All segments of the CMTC should light while the CMTC checks its internal functions. If there are internal failures, the
CMTC will display FAIL. If there is a problem with the CCD communication, the CMTC will display "CCD." Refer to the Compass/Mini-Trip" section
for further diagnosis.
Instrument Cluster
Instrument Cluster
The instrument cluster for Jeep Cherokee (XJ) is available for two different versions: base with two gauges and premium with six gauges. The gauges are
positioned with information received by the cluster over the CCD bus from the PCM. Some of the warning lamps are hardwired and some are controlled
by the cluster using CCD bus information. The vehicle chime function is contained on the cluster circuit board, as well as the timer for the rear window
defogger. There is a self-test available for the cluster that will actuate all the gauges and place them at their calibration points. The test will not run if the
cluster sees engine RPM or vehicle speed. This test will light all CCD controlled lamps for verification of lamp operation. It also forces the odometer
Vacuum Fluorescent (VF) display to count up from all zero's through all nine's. The self-test routine can be entered by pushing and holding the trip reset
button while rotating the ignition key from the "off" to the "on" position, release the button after the test starts.
In the 97 MY, the VF display is also capable of displaying PCM. This feature is accessed the same as in previous years by turning the key from "off" to
"run" three times and staying in position.
The instrument cluster will provide bus bias and termination and the PCM controller provides a second termination. If cluster is disconnected, the bus
will not be biased.
The cluster will be serviced as an assembly. There will be limited parts available: bulbs and sockets, the front lens, the trip odometer stem cover and the
hood and rear cover assembly. No internal parts of the cluster will be serviced.
Normal Operation: At key "on," the cluster will light the low fuel, seat belt, check gauges, check engine, ABS and airbag lamps. As the key is turned
farther toward the "start" position, the brake warning lamp will illuminate. The Vacuum Fluorescent (VF) display will indicate the mileage stored inside
the cluster. If there is a bus failure and the cluster cannot receive distance pulses from the engine controller, the cluster will display the last mileage
stored until the ignition is turned off. If the cluster is receiving bus messages, but is unable to display odometer information because of an internal failure,
the odometer display dashes. VF dimming is handled by the potentiometer that controls instrumentation illumination.
Heated Rear Window Defogger
Heated Rear Window Defogger
The timing circuit for the rear window defogger is contained in the cluster. The operation is as follows: With the ignition on, the first push of the
defogger button will start a 10- minute timer. After 10 minutes have elapsed, the defogger will be turned oft. If the button is pushed a second time during
the same ignition cycle, the timer will turn the defogger on for five minutes. Every consecutive push will operate the defogger for five minutes. When the
defogger is on, it can be turned oft with a second push of the defogger button.
