Page 821 of 2643

ENGINE CONTROLS 1F – 575
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
5Replace the sensor in the affected circuit, if a Diag-
nostic Trouble Code (DTC) was stored for this circuit
(except for the DTCs P0171 and P0172.
Is the repair complete?–System OK–
6Does an intermittent Malfunction Indicator Lamp
(MIL) or DTC occur?–Go toStep 7Go toStep 8
71. Check for a faulty relay, electronic control mod-
ule (ECM) driven solenoid, or switch.
2. Check for improper installation of electrical de-
vices, such as lights, two–way radios, electric
motors, etc.
3. Inspect the ignition control wires for proper
routing (away from ignition wires, ignition sys-
tem components, and the generator).
4. Check for a short–to–ground in the MIL circuit
or the DLC ”test” terminal.
5. Inspect the ECM ground connections.
6. Correct or repair the affected circuits as need-
ed.
Is the repair complete?–System OK–
81. Check for a loss of DTC memory.
2. 2. Disconnect the Throttle Position Sensor.
3. Run the engine at idle until the MIL comes on.
4. Turn the ignition OFF.
Is DTC P0122 stored in memory?–Go toStep 10Go toStep 9
9Replace the ECM.
Is the repair complete?–System OK–
10Does the vehicle stall while driving?–Go toStep 11Go toStep 12
11Monitor the Front Heated Oxygen Sensor (HO2S1)
and the injector base pulse width with the scan tool.
Does the scan tool display a steady low voltage
(about 0 mv) for the HO2S1 sensor with the control
module commanding an injector base pulse width of
the value specified?8 msGo toStep 9Go toStep 12
121. Check for an open diode across the A/C clutch
and for other open diodes.
2. Repair or replace any components as needed.
Is the repair complete?–System OK–
Page 2334 of 2643

AUDIO SYSTEMS 9F – 5
DAEWOO V–121 BL4
FM Radio Does Not Work, AM and Cassette OK
StepActionValue(s)YesNo
11. Unplug the antenna cable from the antenna.
2. Connect the test antenna to the antenna cable.
3. Check the FM radio reception.
Is the FM radio operating properly?–Go to Step 2Go to Step 3
2Replace the antenna.
Is the repair complete?–System OK–
31. Remove the cassette radio from the instrument
panel.
2. Unplug the antenna cable from the audio sys-
tem.
3. Plug the test cable into the audio system.
4. Check the FM radio reception.
Is the FM radio operating properly?–Go to Step 4Go to Step 5
4Replace the antenna cable between the audio sys-
tem and the antenna.
Is the repair complete?–System OK–
5Replace the cassette radio.
Is the repair complete?–System OK–
SPEAKERS
Front Speakers Distorted or Inoperative, Rest of Audio System OK
StepActionValue(s)YesNo
11. Turn the ignition and the radio ON.
2. Check for distorted or inoperative front speak-
ers using the fader and the balance controls
with all of the sources (AM, FM, tape, CD).
Are the front speakers distorted?–Go to Step 2Go to Step 4
2Check the speaker and the door area for damage,
rattles, or vibration.
Is there anything loose or in the way of the speaker
causing the distortion?–Go to Step 3Go to Step 4
3Make the necessary repairs to secure the compo-
nent causing the distortion.
Is the repair complete?–System OK–
41. Remove the front speakers and disconnect the
speaker connector.
2. Using an ohmmeter, test the speaker wires for
a short to ground.
Does the ohmmeter show the specified value?Go to Step 6Go to Step 5
5Repair the short circuit between the front speaker
connector and the radio connector.
Is the repair complete?–System OK–
6Substitute a known good speaker for the speaker
causing the distortion.
Is the distortion eliminated?–Go to Step 7Go to Step 8
Page 2335 of 2643

9F – 6IAUDIO SYSTEMS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
7Replace the speaker.
Is the repair complete?–System OK–
8Replace the cassette radio.
Is the repair complete?–System OK–
Rear Speakers Distorted or Inoperative, Rest of Audio System OK
StepActionValue(s)YesNo
11. Turn the ignition and the radio on.
2. Check for distorted or inoperative rear speak-
ers using the fader and the balance controls
with all the of the sources (AM, FM, tape, CD).
Are the rear speakers distorted?–Go to Step 2Go to Step 4
2Check the speakers, the rear deck, and the trunk
area for damage, rattles, or vibration.
Is there anything loose or in the way of the speaker
causing the distortion?–Go to Step 3Go to Step 4
3Make the necessary repairs to secure the compo-
nent causing the distortion.
Is the repair complete?–System OK–
41. Disconnect the rear speakers.
2. Using an ohmmeter, test the speaker wires for
a short to ground.
Does the ohmmeter show the specified value?Go to Step 6Go to Step 5
5Repair the short circuit between the rear speaker
connector and the radio connector.
Is the repair complete?–System OK–
6Substitute a known good speaker for the speaker
causing the distortion.
Is the distortion eliminated?–Go to Step 7Go to Step 8
7Replace the speaker.
Is the repair complete?–System OK–
8Replace the audio system.
Is the repair complete?–System OK–