Speakers Inoperative - One or More. Chevrolet Corvette 1999

Are both of the front midrange speakers inoperative?

Go to Step 3

Turn the ignition switch to OFF.
Disconnect the inoperative speaker connector.
Using a DMM, measure the resistance across the speaker from terminal D to terminal E.

Is the resistance between the specified values?

3-6ohms

Go to Step 4

Disconnect the radio connector C1.
Using a DMM, measure the resistance at the inoperative speaker connector from terminal D to ground.

Is the measured resistance to ground infinite?

Go to Step 5

Go to Step 6

Using a DMM, measure the resistance at the speaker connector from terminal E to ground.

Is the measured resistance to ground infinite?

Go to Step 7

Repair a short to ground in the speaker feed CKT 200 or CKT 201 (see schematic) depending on which side was tested.

Is the repair complete?

Repair a short to ground in the speaker return for CKT 117 or CKT 118 (see schematic) depending on which side was tested.

Is the repair complete?

Check for continuity in the speaker feed circuit:

•	(Left side) Using a DMM, check for continuity between the radio connector C1 terminal 2 and the LH front speaker connector terminal D.

•	(Right side) Using a DMM, check for continuity between the radio connector C1 terminal 4 and the RH front speaker connector terminal D.

Is continuity present between these terminals?

Check for continuity in the speaker return circuit:

•	(Left side) Using a DMM, check for continuity between the radio connector C1 terminal 1 and the LH front speaker connector terminal E.

•	(Right side) Using a DMM, check for continuity between the radio connector C1 terminal 3 and the RH front speaker connector terminal E.

Is continuity present between these terminals?

Go to Step 13

Go to Step 11

Repair the open in:

•	Right side = CKT 200.

•	Left side = CKT 201.

Is the repair complete?

Repair the open in:

•	Right side = CKT 117.

•	Left side = CKT 118.

Is the repair complete?

Replace the inoperative speaker. Refer to Radio Front Speaker Replacement .

Is the repair complete?

Replace the radio. Refer to Radio Replacement .

Is the repair complete?

Speakers Inoperative - One or More Front Subwoofers

One or Two Subwoofer(s) are Inoperative

Step

Action

Value(s)

Yes

DEFINITION: Either one or both of the front amplified subwoofers are not operating correctly.

Where you sent here from the Radio/Audio System Check?

Go to Step 2

Are both of the front amplified subwoofers inoperative?

Go to Step 19

Go to Step 3

Disconnect the inoperative speaker connector.
Turn the ignition switch to ON.
Turn the radio ON.
Connect a test light between the speaker connector terminal A and ground.

Does the test light illuminate?

Go to Step 4

Connect a test light from the speaker connector from terminal H to ground.

Does the test light illuminate?

Go to Step 5

Connect a test light from the speaker connector from terminal A to terminal B.

Does the test light illuminate?

Go to Step 6

Connect a test light from the speaker connector from terminal A to terminal G.

Does the test light illuminate?

Go to Step 7

Turn the radio to OFF.
Turn the ignition switch to OFF.
Disconnect the Bose® Signal Processor connector.
Connect a DMM between the speaker connector terminal C and ground.
Measure the resistance to ground at the speaker connector terminal C.

Is the resistance infinite?

Go to Step 11

Connect a DMM between the speaker connector terminal F and ground.
Measure the resistance to ground at the speaker connector terminal F.

Is the resistance infinite?

Go to Step 13

Repair the open in CKT 360.

Is the repair complete?

Repair the open in CKT 351 between the inoperative speaker connector and G201.

Is the repair complete?

Repair the short to ground in:

•	Right side = CKT 1726.

•	Left side = CKT 1725.

Is the repair complete?

Repair the short to ground in:

•	Right side = CKT 512.

•	Left side = CKT 511.

Is the repair complete?

Reconnect the Bose® Signal Processor connector.
Connect a DMM between the speaker connector terminal C and terminal F.
Set the DMM to the low AC voltage scale between 0 and 10 volts.
Turn the ignition switch to ON.
Tune the radio to a strong station and set the volume to medium.
Adjust the Fade control to the suspect speaker.

Does the DMM read a varying voltage of approximately 0.1 to 2.0 volts?

Go to Step 14

Go to Step 15

Replace the inoperative speaker. Refer to Radio Front Speaker Replacement .

Is the repair complete?

Turn the radio to OFF.
Turn the ignition switch OFF.
Disconnect the Bose® Signal Processor connector.
(Left side) Using a DMM, measure for continuity between the:

•	(Left side) speaker connector terminal C and the Bose® Signal Processor connector terminal A3.

•	(Right side) speaker connector terminal C and the Bose® Signal Processor connector terminal A9.

Is the CKT 1725 or CKT 1726 continuous between the speaker and Bose® Signal Processor connectors?

Go to Step 16

Go to Step 25

Using a DMM, measure for continuity between the:

•	(Left side) speaker connector terminal F and the Bose® Signal Processor connector terminal B11.

•	(Right side) speaker connector terminal F and the Bose® Signal Processor connector terminal A11.

Is the CKT 511 or CKT 512 continuous between the speaker and Bose® Signal Processor connectors?

Go to Step 17

Go to Step 26

Connect a DMM between the:

•	(Left side) Bose® Signal Processor connector terminal A4 and terminal B5.

•	(Right side) Bose® Signal Processor connector terminal B7 and terminal A4.

Set the DMM to the low AC voltage scale between 0 and 10 volts.
Turn the ignition switch to ON.
Tune the radio to a strong station and set the volume to medium.
Adjust the Fade control to the suspect speaker.

Does the DMM read a varying voltage of approximately 0.1 to 2.0 volts?

Go to Step 18

Go to Step 19

Connect a DMM between the:

•	(Left side) Bose® Signal Processor connector terminal A4 and terminal B6.

•	(Right side) Bose® Signal Processor connector terminal B8 and terminal A4.

Set the DMM to the low AC voltage scale between 0 and 10 volts.
Turn the ignition switch to ON.
Tune the radio to a strong station and set the volume to high.
Adjust the Fade control to the suspect speaker.

Does the DMM read a varying voltage of approximately 0.1 to 2.0 volts?

Go to Step 23

Go to Step 20

Turn the radio to OFF.
Turn the ignition switch OFF.
Disconnect the radio connector C4.
Using a DMM, measure for continuity between the:

•	(Left side) radio connector C4 terminal 9 and the Bose® Signal Processor connector terminal B5.

•	(Right side) radio connector C4 terminal 10 and the Bose® Signal Processor connector terminal B7.

Is the CKT 511 or CKT 512 continuous between the radio and Bose® Signal Processor connectors?

Go to Step 21

Go to Step 26

Turn the radio to OFF.
Turn the ignition switch OFF.
Disconnect the radio connector C4.
Using a DMM, measure for continuity between the:

•	(Left side) radio connector C4 terminal 11 and the Bose® Signal Processor connector terminal B6.

•	(Right side) radio connector C4 terminal 12 and the Bose® Signal Processor connector terminal B8.

Is the CKT 599 or CKT 546 continuous between the radio and Bose® Signal Processor connectors?

Go to Step 22

Go to Step 27

Using a DMM, measure the resistance between the:

•	(Left side) radio connector C4 terminal 9 and ground.

•	(Right side) radio connector C4 terminal 10 and ground.

Is the resistance infinite?

Go to Step 24

Using a DMM, measure the resistance between the:

•	(Left side) radio connector C4 terminal 11 and ground.

•	(Right side) radio connector C4 terminal 12 and ground.

Is the resistance infinite?

Go to Step 24

Go to Step 28

Replace the Bose® Signal Processor. Refer to Bose Module Replacement .

Is the repair complete?

Replace the radio. Refer to Radio Replacement .

Is the repair complete?

Repair the open in:

•	Right side = CKT 1726.

•	Left side = CKT 1725.

Is the repair complete?

Repair the open in:

•	Right side = CKT 512.

•	Left side = CKT 511.

Is the repair complete?

Repair the open in:

•	Left side = CKT 599.

•	Right side = CKT 546.

Is the repair complete?

Repair the short to ground in:

•	Left side = CKT 599.

•	Right side = CKT 546.

Is the repair complete?

Speakers Inoperative - One or More Rear Speakers

One or Two Rear Speaker(s) are Inoperative

Step

Action

Value(s)

Yes

DEFINITION: Either one or both of the rear speakers are not operating correctly.

Where you sent here from the Radio/Audio System Check?

Go to Step 2

Are both of the rear speakers inoperative?

Go to Step 3

Turn the ignition switch to OFF.
Disconnect the inoperative speaker connector.
Using a DMM, measure the resistance across the speaker from terminal A to terminal B.

Is the resistance between the specified values?

3-6ohms

Go to Step 4

Disconnect the radio connector C2.
Using a DMM, measure the resistance at the inoperative speaker connector from terminal B to ground.

Is the measured resistance to ground infinite?

Go to Step 5

Go to Step 6

Using a DMM, measure the resistance at the speaker connector from terminal A to ground.

Is the measured resistance to ground infinite?

Go to Step 7

Repair a short to ground in the speaker feed CKT 199 or CKT 46 (see schematic) depending on which side was tested.

Is the repair complete?

Repair a short to ground in the speaker return for CKT 116 or CKT 115 (see schematic) depending on which side was tested.

Is the repair complete?

Check for continuity in the speaker feed circuit:

•	(Left side) Using a DMM, check for continuity between the radio connector C2 terminal 20 and the LH rear speaker connector terminal B.

•	(Right side) Using a DMM, check for continuity between the radio connector C2 terminal 18 and the RH rear speaker connector terminal B.

Is continuity present between these terminals?

Check for continuity in the speaker return circuit:

•	(Left side) Using a DMM, check for continuity between the radio connector C2 terminal 19 and the LH front speaker connector terminal A.

•	(Right side) Using a DMM, check for continuity between the radio connector C2 terminal 17 and the RH front speaker connector terminal A.

Is continuity present between these terminals?

Go to Step 13

Go to Step 11

•	(Right side) Repair the open in CKT 46.

•	(Left side) Repair the open in CKT 199.

Is the repair complete?

•	(Right side) Repair the open in CKT 115.

•	(Left side) Repair the open in CKT 116.

Is the repair complete?

Replace the inoperative speaker. Refer to Radio Rear Speaker Replacement .

Is the repair complete?

Replace the radio. Refer to Radio Replacement .

Is the repair complete?