Wrangler 4WD L4-150 2.5L VIN P MFI (1998)
Speaker: Testing and Inspection
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIRBAGS 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.
CAUTION: The speaker output of the radio is a "floating ground" system. Do not allow any speaker lead to short to ground, as damage to the radio
may result.
1. Turn the ignition switch to the On position. Turn the radio on. Adjust the balance and fader controls to check the performance of each individual
speaker. Note the speaker locations that are not performing correctly. Go to Step 2.
2. Turn the radio off. Disconnect and isolate the battery negative cable. Remove the radio. Unplug the wire harness connectors at the radio. Check
both the speaker feed (+) circuit and return (-) circuit cavities for the inoperative speaker location(s) at the radio wire harness connectors for
continuity to ground. In each case, there should be no continuity. If OK, go to Step 4. If not OK, go to Step 3.
3. Leave the radio wire harness connectors unplugged. Unplug the wire harness connector at the inoperative speaker. Check both the speaker feed (+)
circuit and return (-) circuit cavities of the speaker wire harness connector for continuity to ground. In each case, there should be no continuity If
OK, replace the shorted speaker. If not OK, repair the shorted circuit as required.
4. Plug in the speaker wire harness connector. Check the resistance between the speaker feed (+) circuit and return (-) circuit cavities of the radio
wire harness connectors for the inoperative speaker location(s). The meter should read between 3 and 8 ohms (speaker resistance). If OK, go to
Step 5. If not OK, go to Step 6.
5. Install a known good radio. Connect the battery negative cable. Turn the ignition switch to the On position. Turn on the radio and test the speaker
operation. If OK, replace the faulty radio. If not OK, replace the faulty speaker.
6. Turn the radio off. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Remove the test radio. Unplug
the speaker wire harness connector at the inoperative speaker. Check the resistance between the speaker feed (+) circuit cavities of the radio wire
harness connector and the speaker wire harness connector. Repeat the check between the speaker return (-) circuit cavities of the radio wire
harness connector and the speaker wire harness connector. In each case, there should be no measurable resistance. If OK, replace the faulty
speaker. If not OK, repair the speaker wire harness circuit(s) as required.