Audio and Visual System

AUDIO / VISUAL: AUDIO AND VISUAL SYSTEM: 74-40: Short in Speaker Circuit

DTC 74-40 - Short in Speaker Circuit

DESCRIPTION





This circuit has a fail-safe function.

- When a short in the speaker circuit is detected, all sound outputs are stopped.

WIRING DIAGRAM













INSPECTION PROCEDURE
HINT: After the inspection is completed, clear the DTCs.

PROCEDURE

1. INSPECT STEREO COMPONENT AMPLIFIER




(a) Disconnect the stereo component amplifier connectors M31 and M32.
(b) Clear the DTCs and recheck for DTCs.
(c) Check if DTC 74-40 is output.
OK:
DTC 74-40 is not output.
NG -- REPLACE STEREO COMPONENT AMPLIFIER
OK -- Continue to next step.
2. CHECK OPERATION
(a) Reconnect the stereo component amplifier connector M31.
(b) Check if DTC 74-40 is output.
OK:
DTC 74-40 is not output.
NG -- CHECK HARNESS AND CONNECTOR
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR




(a) Disconnect the connectors shown in the illustration from the stereo component amplifier and speakers.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





*1: with Rear Header Speaker
*2: without Rear Header Speaker
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CONFIRM MODEL
Result:






B -- INSPECT FRONT STEREO COMPONENT SPEAKER
A -- Continue to next step.
5. INSPECT FRONT STEREO COMPONENT SPEAKER
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 8 Ohms
NG -- REPLACE FRONT STEREO COMPONENT SPEAKER
OK -- Continue to next step.
6. INSPECT STEREO COMPONENT SPEAKER




(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:






NG -- REPLACE STEREO COMPONENT SPEAKER
OK -- Continue to next step.
7. INSPECT REAR HEADER SPEAKER (LEFT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 8 Ohms
NG -- REPLACE REAR HEADER SPEAKER (LEFT HAND)
OK -- Continue to next step.
8. INSPECT REAR HEADER SPEAKER (RIGHT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 8 Ohms
NG -- REPLACE REAR HEADER SPEAKER (RIGHT HAND)
OK -- REPLACE FRONT NO. 1 SPEAKER (LEFT HAND)
9. INSPECT FRONT STEREO COMPONENT SPEAKER
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 10 Ohms
NG -- REPLACE FRONT STEREO COMPONENT SPEAKER
OK -- REPLACE STEREO COMPONENT SPEAKER
10. CHECK HARNESS AND CONNECTOR




(a) Disconnect the connectors shown in the illustration from the stereo component amplifier and speakers.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





*1: with Rear Header Speaker
*2: without Rear Header Speaker
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
11. CONFIRM MODEL
Result:






B -- INSPECT FRONT NO. 1 SPEAKER (LEFT HAND)
A -- Continue to next step.
12. INSPECT FRONT NO. 2 SPEAKER (LEFT HAND)
(a) Reconnect the stereo component amplifier connector and front No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE FRONT NO. 2 SPEAKER (LEFT HAND)
OK -- Continue to next step.
13. INSPECT FRONT NO. 2 SPEAKER (RIGHT HAND)
(a) Reconnect the stereo component amplifier connector and front No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE FRONT NO. 2 SPEAKER (RIGHT HAND)
OK -- Continue to next step.
14. INSPECT REAR SPEAKER (LEFT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 8 Ohms
NG -- REPLACE REAR SPEAKER (LEFT HAND)
OK -- Continue to next step.
15. INSPECT REAR SPEAKER (RIGHT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 8 Ohms
NG -- REPLACE REAR SPEAKER (RIGHT HAND)
OK -- Continue to next step.
16. INSPECT REAR NO. 2 SPEAKER (LEFT HAND)
(a) Reconnect the stereo component amplifier connector and rear No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE REAR NO. 2 SPEAKER (LEFT HAND)
OK -- Continue to next step.
17. INSPECT REAR NO. 2 SPEAKER (RIGHT HAND)
(a) Reconnect the stereo component amplifier connector and rear No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE REAR NO. 2 SPEAKER (RIGHT HAND)
OK -- REPLACE FRONT NO. 1 SPEAKER (RIGHT HAND)
18. INSPECT FRONT NO. 1 SPEAKER (LEFT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 4 Ohms
NG -- REPLACE FRONT NO. 1 SPEAKER (LEFT HAND)
OK -- Continue to next step.
19. INSPECT FRONT NO. 1 SPEAKER (RIGHT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 4 Ohms
NG -- REPLACE FRONT NO. 1 SPEAKER (RIGHT HAND)
OK -- Continue to next step.
20. INSPECT FRONT NO. 2 SPEAKER (LEFT HAND)
(a) Reconnect the stereo component amplifier connector and front No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE FRONT NO. 2 SPEAKER (LEFT HAND)
OK -- Continue to next step.
21. INSPECT FRONT NO. 2 SPEAKER (RIGHT HAND)
(a) Reconnect the stereo component amplifier connector and front No. 2 speaker connector.
(b) Check that audio sound can be heard from the speaker.
OK:
Audio sound can be heard.
NG -- REPLACE FRONT NO. 2 SPEAKER (RIGHT HAND)
OK -- Continue to next step.
22. INSPECT REAR SPEAKER (LEFT HAND)
(a) Resistance check.
(1) Measure the resistance between the terminals of the speaker.
Standard resistance:
Approximately 4 Ohms
NG -- REPLACE REAR SPEAKER (LEFT HAND)
OK -- REPLACE REAR SPEAKER (RIGHT HAND)