drw6895

I have a 2004 Lexus LS 430 with 88,000 miles on it with the Navigation System & ML Sound System. The audio buttons & climate buttons on the Navigation controls only work intermittently, and frequently do not work at all. When you hit the buttons nothing happens Other times, they function normally. The smart key on the car has also stopped working all together.

I had a IPod connector installed in the car about a month ago at a cost of $425. Not sure if this is contributing factor or not. The climate & audio controls have worked since this was done, but also still fail intermittently. I have had the car into Lexus and they disconnected the IPOD connector and told me this would solve my problem, but the climate & audio buttons still do not work consistently (work less than they did before).

Lexus replaced the batteries in the SMART key and this had zero impact on correcting the issue. The SMART key was not working prior to installation of the IPOD connector, so this had nothing to do with it.

Any ideas on solutions would be appreciated. I am wondering if the NAV unit is going bad.

Thanks,

Dale

Owczar

Do you have a problem with button on touch screen also? Or you have problem only with buttons on navigation panel?
Is this problems appear together? I mean smart key problem and problem with navigation buttons.

Where the ipad was connected? To the navi ECU on the trunk?
Do you have any problems before ipad installation?

drw6895

The buttons on the Navigation screen (where the map is) appear to work fine. My problems are on the plastic buttons to the right of the Navigation screen. The Plastic buttons are titled: Climate, Audio, and Options.

On the ride home tonight, all of the buttons magically started working again, even though they were out most of the day and I made multiple trips in the car. It is the goofiest problem.

drw6895

It is connected in the front of the car. The harness appears to fit the Lexus harness. My problems returned again today. Car worked fine this morning, I drove it for a few hours and the Climate & Audio buttons quit working again.

Tom57

How long have you owned the car? Has it been in storage/not used for a time?

Owczar

I found that it could be (or must be) gateway ECU. Only this ECU (Multiplex Communication System) is communicating and transferring signals from Nav Panel to Audio and climate ECU. It also responsible for smart key system.

Maybe it is something wrong with harness connectors or gateway ECU malfunction.

drw6895

The car is usually driven on the weekends during decent weather. I have a Company car that I drive to work. The car has 88,000 miles and is garaged every day.

drw6895

This is helpful since the smart key is also acting up. I have to use the key to start the car. The Lexus dealer doesn't want to check the harnesss since the iPod adapter is aftermarket, even though it is unplugged. Would the gateway ECU have anything to do with needing to replace the Nav Unit itself? I don't know much about the electronics on this car and I have concerns about the knowledge level of the Lexus Service technician in Cincinnati.

Thanks,

Dale