Ml System Defective, Please Help

[IalexI]

Hi Guys,

I have a 2001 LS430 whose audio system has some issues.

I have the ML audio system and an old handsfree telephone option from Siemens.

First, there was some erratic noise even if the radio/cd was switched off. This changed a few days ago: When I start the car, I can hear sound for a few seconds and the the sound completely switches off.

What I have done so far:

- My amp was defective last year and I have sent it to the repair shop which did the repair (I had a 1 year warrany on their work). I believe they are very professional (actually, they are specialised on Lexus amps). They verified that the amp is working fine.

- I removed the handsfree telephone module. I haven't found the relay, yet, for the mute wire.

- When I got the amp back, I disconnected one of the 3 wire harnesses just to figure out if I can trace back where the erratic noise comes from (navigation, radio?). I believe it comes from the radio. Since I did this, the error changed (car starts -> a few seconds sound -> silence).

- I bought a new radio/cd and installed it. The error did not change.

Questions:

- Could I have damaged something by disconnecting the wire harnesses?

- How can I get into the diagnostic menu? I am not sure what is meant by "info switch". I have a "Option" switch and when I click on it, I have a "Information" button on the touch screen. Is this meant by "Info switch"?

- How can I locate the mute wire? Where does it go (amp/radio) and which pins are used?

Thank you for your help

Alex

[jainla]

Siemens? It sounds like it may be an aftermarket install. Was this car sold in the USA?

When you removed the module what did you remove exactly? The cradle that holds the phone? Or the brain that runs the system? Also do you know if the car has the old Lexus Link system installed? If you see buttons on the sunglass holder and they light up at night, it's still connected.

OEM manufacturer for the HF system in '01/02 was Denso with a Qualcomm phone. For one year, '03 a Nokia 6310 phone was fitted onto the Denso system via a Junction box. Then in '04 the system went Bluetooth only.

The OEM phone module is in the trunk, on the left side under the floor. If you see a box there under the panel to the left of the tire well then you may have the OEM system. The power/speaker/relay connector is on the right side, also under the floor; the wiring runs under the trim across the back of the trunk and then behind the GPS and Radio system.

Attached is a photo showing the attach point (it's the connector marked with the X). The car shown has the Lexus Link system installed. This is the power/audio/mute point for both the phone and LL system (they are connected in serial). Try disconnecting whatever is connected to this (one half of the connector should be fixed to the car, that's the one you should unplug) and see if this solves your problem.

If you have an aftermarket system then it might be harder to find the mute point. The connectors on the back of the cd/radio have 2 wires marked as mute wires, one seems to come from the phone and one seems to go to the amplifier.

Does the CD/Tape player work at all? Or is it all dead? I would pull the head unit and see if anything appears to be attached to the harness back there.

Hi Guys,

I have a 2001 LS430 whose audio system has some issues.

I have the ML audio system and an old handsfree telephone option from Siemens.

First, there was some erratic noise even if the radio/cd was switched off. This changed a few days ago: When I start the car, I can hear sound for a few seconds and the the sound completely switches off.

What I have done so far:

- My amp was defective last year and I have sent it to the repair shop which did the repair (I had a 1 year warrany on their work). I believe they are very professional (actually, they are specialised on Lexus amps). They verified that the amp is working fine.

- I removed the handsfree telephone module. I have found the relay, yet, for the mute wire.

- When I got the amp back, I disconnected one of the 3 wire harnesses just to figure out if I can trace back where the erratic noise comes from (navigation, radio?). I believe it comes from the radio. Since I did this, the error changed (car starts -> a few seconds sound -> silence).

- I bought a new radio/cd and installed it. The error did not change.

Questions:

- Could I have damaged something by disconnecting the wire harnesses?

- How can I get into the diagnostic menu? I am not sure what is meant by "info switch". I have a "Option" switch and when I click on it, I have a "Information" button on the touch screen. Is this meant by "Info switch"?

- How can I locate the mute wire? Where does it go (amp/radio) and which pins are used?

Thank you for your help

Alex

[IalexI]

Hi Jainla,

Thank you for your reply.

It's a German LS430; from what I read so far, there seem to be some differences.

First of all, it does not have Lexus Link. Also, there was no option to get a factory fitted phone here.

The Siemens phone is aftermarket and I have removed the "brain" of the system. I am not sure, if there is still a relay in the car (I haven't found it), which might trigger the mute wire.

If I start the car, I can hear radio/CD (and probably tape) sound just fine for a couple of seconds, before it gets muted. Do you have a wiring diagramm or can at least tell me which pins connect to the mute wire? Honestly, I have a hard time to follow all the cables and I am not sure which cables from the phone go to the radio.

I have also noticed that one of the speakers seems to be dead (the left speaker on the back). I only have some seconds of sound, when I start the car, but this was enough to evaluate if the speakers are functional by adjusting the balance/fading of the radio.

Could it be possible that this speaker causes all the trouble?

Best,

Alex

[jainla]

The left rear door speaker is the OEM speaker for the phone and Lexus Link system. The junction point in the trunk contains the wiring for that speaker.

For the OEM system there is a relay that disconnects the speaker from the amp and connects it to the amp inside the Telephone ECU (or the LL ECU).

It's possible that the aftermarket installer either tapped the wiring in the door or ran wiring back to the trunk to access that junction point. Where was the ECU located? If you plug it back in does the sound in the left rear speaker come back?

I think I might have a wiring diagram somewhere. I know there is a mute wire on the back of the tape/CD player harness, you might have to follow the wires out of the Siemens ECU and see where they go. Can you post some photos?

Hi Jainla,

Thank you for your reply.

It's a German LS430; from what I read so far, there seem to be some differences.

First of all, it does not have Lexus Link. Also, there was no option to get a factory fitted phone here.

The Siemens phone is aftermarket and I have removed the "brain" of the system. I am not sure, if there is still a relay in the car (I haven't found it), which might trigger the mute wire.

If I start the car, I can hear radio/CD (and probably tape) sound just fine for a couple of seconds, before it gets muted. Do you have a wiring diagramm or can at least tell me which pins connect to the mute wire? Honestly, I have a hard time to follow all the cables and I am not sure which cables from the phone go to the radio.

I have also noticed that one of the speakers seems to be dead (the left speaker on the back). I only have some seconds of sound, when I start the car, but this was enough to evaluate if the speakers are functional by adjusting the balance/fading of the radio.

Could it be possible that this speaker causes all the trouble?

Best,

Alex

[IalexI]

Hi Jainla,

The ECU of the telephone was installed in the center arm rest. I believe its sound came from the front right speaker.. nonetheless, I will test if I can reactivate the left back speaker by reinstalling it.

Of course, I can take pictures (the car really looks horrible!). Please let me know what exactly would be of interest for you.

Best,

Alex

[jainla]

I think a photo of the inside of the center console (with the wiring for the ECU) and then a photo of the junction point on the right side of the trunk would do for a start. Let's see what's in there...

Hi Jainla,

The ECU of the telephone was installed in the center arm rest. I believe its sound came from the front right speaker.. nonetheless, I will test if I can reactivate the left back speaker by reinstalling it.

Of course, I can take pictures (the car really looks horrible!). Please let me know what exactly would be of interest for you.

Best,

Alex