Weird Issue With The Sound System...

[MSlave]

I'm wondering if someone else has had a similar experience to this, or have any light they could shed on it.

I have a 93 Lexus LS400, with the Nakamichi sound system, without the phone.

Everything works great in her, until I need to slam on the brakes quite hard - then the sound system stops working.

It usually happens right after I slam the brakes on, but sometimes for 10-15 minutes after the fact. The volume on the sound system goes to ALMOST mute, if I turn to max volume I can faintly here the music. This goes for both the CD and radio.

Within a few hours, the sound system comes back and preforms as it should. "Normal" braking is fine, its only when I apply quite a bit of pressure to them that this happens.

I have no idea why the brakes would have such a dire effect on a seemingly unrelated system? It would appear to me like there is a short circuit somewhere, but why would it only short out when I slam the brakes? And why would it come back randomly after a few hours?

Any ideas?

Cheers

Josh

[bigste]

No idea but brake wires go through the trunk hinge harness and that is a problem on these cars.

[Alexander the o.k.]

The next symptom will be the stalling/ sputtering/ dieing issue.

Save yourself the aggravation of replacing needless parts, false diagnosyses (read guesses) and hours/ days spent in the shop.

Our friend above is correct.

Here's what to do:

1-Open the trunk,

2-Observe the wire harness movement at the left hinge as you open/close the lid.

(this will help you pinpoint the spot in the harness that has become frayed/fatigued).

3- Remove the wire harness cover.

4-Strip off all the tape, etc.

5- Look for breaks or near breaks in the wires. You will find at least one. That is your stereo circuit.

It has obviously not broken completely or you would hear no sound at all.

6-Re-connect, then re-wrap each wire individually, then wrap the whole into one bundle to reinforce it. Let it swing freely in the trunk.

7-Make sure that when you are finished with the repair, that you route the whole mess such that there is as little movement/tension on it as open or shut the lid.

It is this action that caused the short to occur in the first place.

After years of repeated tension the wires will start to fatigue and break.

This is a design flaw that most dealers should be aware of.

Hope this helps.

Good luck.

[MSlave]

The next symptom will be the stalling/ sputtering/ dieing issue.

Save yourself the aggravation of replacing needless parts, false diagnosyses (read guesses) and hours/ days spent in the shop.

Our friend above is correct.

Here's what to do:

1-Open the trunk,

2-Observe the wire harness movement at the left hinge as you open/close the lid.

(this will help you pinpoint the spot in the harness that has become frayed/fatigued).

3- Remove the wire harness cover.

4-Strip off all the tape, etc.

5- Look for breaks or near breaks in the wires. You will find at least one. That is your stereo circuit.

It has obviously not broken completely or you would hear no sound at all.

6-Re-connect, then re-wrap each wire individually, then wrap the whole into one bundle to reinforce it. Let it swing freely in the trunk.

7-Make sure that when you are finished with the repair, that you route the whole mess such that there is as little movement/tension on it as open or shut the lid.

It is this action that caused the short to occur in the first place.

After years of repeated tension the wires will start to fatigue and break.

This is a design flaw that most dealers should be aware of.

Hope this helps.

Good luck.

Thanks, I will try this. I know this has been looked at before and I have taped up some of the wires in the hinge, but maybe I did not do a good enough job?

Does anyone know what color the wiring for the stereo is?

[MSlave]

I patched up the hinge wires again last night, but it did not fix the problem.

I also looked at both fuses responsible for the stereo circut, but they appear to be fine.

Anyone else have any ideas as to what it could be? It hasn't worked at all lately (I think the problem may be related to the fact that we have had a steady 2.5 weeks of rain, and something may be damp??)

[eatingupblacktop]

Could be a loose connection that breaks on hard braking. Comes back after the car has been driven enough for the vibrations to reestablish contact.

[Alexander the o.k.]

Josh,

Do you have any other weird electrical issues?

Any of the typical probs associated with the wire harness issue such as dash lights, rough idle, etc?

If not, then I suggest checking and cleaning the battery terminals and make sure they are rock solid tight. put a little silicone on each after cleaning all debris.

[Alexander the o.k.]

Try this :

http://www.carstereohelp.com/repairDoItYou...usRepairVol.htm

And scroll down.

Apparently, this is a known issue w the LS line.

It may or may not apply in your case.

[eatingupblacktop]

Try this :

http://www.carstereohelp.com/repairDoItYou...usRepairVol.htm

And scroll down.

Apparently, this is a known issue w the LS line.

It may or may not apply in your case.

Good work a.o.k. Had this bookmarked but haven't had a chance to check it out. Thanks for reminding me.

[Alexander the o.k.]

My pleasure.

You guys have helped more than you know.