Grand Cherokee 2WD V8-4.7L VIN N (2000)
CD Changer: Testing and Inspection
Following are tests that will help to diagnose the hard wired components and circuits of the Compact Disc (CD) changer unit. However, these tests may
not prove conclusive in the diagnosis of this unit. In order to obtain conclusive testing of the CD changer unit, the Programmable Communications
Interface (PCI) data bus network, the CD changer unit, the radio receiver unit and any other electronic modules that provide inputs to, or receive outputs
from the audio system must be checked.
The most reliable, efficient, and accurate means to diagnose the CD changer messaging functions requires the use of a DRB scan tool and the proper
Diagnostic Procedures. The DRB scan tool can provide confirmation that the PCI data bus is functional, that all of the electronic modules in the vehicle
are sending and receiving the proper messages on the PCI data bus, and that the CD changer and the radio receiver are receiving the proper PCI
messages to perform their audio system functions.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIR BAGS AND SEAT BELTS/AIR BAGS BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE.
FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
Compact Disc Changer Inoperative
1. Turn the ignition switch to the On position. Turn the radio receiver on and check its operation. If OK, go to Step 2. If not OK, refer to Radio
Receiver in the Diagnosis and Testing.
2. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Disconnect the right body wire harness connector
from the CD changer connector receptacle. Check for continuity between the power ground (Z17) circuit of the right body wire harness connector
for the CD changer and a good ground. There should be continuity. If OK, go to Step 3. If not OK, repair the open power ground circuit to the
radio receiver as required.
3. Reconnect the battery negative cable. Check for battery voltage at the B(+) circuit cavity of the right body wire harness connector for the CD
changer. If OK, go to Step 4. If not OK, go to Step 5.
4. Turn the ignition switch to the On position. Check for battery voltage at the ignition switch output circuit cavity of the right body wire harness
connector for the CD changer. If OK, use a DRB scan tool and the proper Diagnostic Procedures for further diagnosis. If not OK, go to Step 6.
5. Disconnect and isolate the battery negative cable. Remove the radio receiver from the instrument panel. Disconnect the DIN cable connector (C4)
from the radio receiver, but do not disconnect the other wire harness connectors. Reconnect the battery negative cable. Check for battery voltage at
the B(+) circuit cavity of the DIN connector receptacle on the radio receiver. If OK, repair the open B(+) circuit to the CD changer as required. If
not OK, check for a shorted B(+) circuit to the CD changer and repair as required, then replace the faulty radio receiver.
6. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Remove the radio receiver from the instrument
panel. Disconnect the DIN cable connector (C4) from the radio receiver, but do not disconnect the other wire harness connectors. Reconnect the
battery negative cable. Turn the ignition switch to the On position. Check for battery voltage at the ignition switch output circuit cavity of the DIN
connector receptacle on the radio receiver. If OK, repair the open ignition switch output circuit to the CD changer as required. If not OK, check for
a shorted ignition switch output circuit to the CD changer and repair as required, then replace the faulty radio receiver.
No Sound Or Only One Channel Sound From CD
1. Turn the ignition switch to the On position. Turn the radio receiver on and check its audio output operation. If OK, go to Step 2. If not OK, refer to
Speaker in the Diagnosis and Testing.
2. Disconnect and isolate the battery negative cable. Disconnect the right body wire harness connector from the CD changer connector receptacle.
Remove the radio receiver from the instrument panel. Disconnect the DIN cable connector (C4) from the radio receiver. Check for continuity
between the audio ground (Z4) circuit cavity of the right body wire harness connector for the CD changer and a good ground. There should be no
continuity. If OK, go to Step 3. If not OK, repair the shorted audio ground (Z4) circuit as required.
3. Check for continuity between the audio ground (Z4) circuit cavity of the right body wire harness connector for the CD changer and the audio
ground (Z4) circuit pin of the DIN cable connector for the radio receiver. There should be continuity. If OK, go to Step 4. If not OK, repair the
open audio ground (Z4) circuit as required.
4. Check for continuity between the audio out right circuit cavity of the right body wire harness connector for the CD changer and a good ground.
There should be no continuity. If OK, go to Step 5. If not OK, repair the shorted audio out right circuit as required.
5. Check for continuity between the audio out right circuit cavity of the right body wire harness connector for the CD changer and the audio out right
circuit pin of the DIN cable connector for the radio receiver. There should be continuity. If OK, go to Step 6. If not OK, repair the open audio out
right circuit as required.
6. Check for continuity between the audio out left circuit cavity of the right body wire harness connector for the CD changer and a good ground.
There should be no continuity. If OK, go to Step 7. If not OK, repair the shorted audio out left circuit as required.
7. Check for continuity between the audio out left circuit cavity of the right body wire harness connector for the CD changer and the audio out left
circuit pin of the DIN cable connector for the radio receiver. There should be continuity. If OK, replace the faulty CD change. If not OK, repair
the open audio out left circuit as required.
