1994 Gs300 Premium Sound Problem

[Luis Arnel]

Need your advice: I has problem with the radio of my Lexus, it has all functions and the display is ok, but suddenly no sound comes out. The fuses are not blown. The premium sound description is AM FM, Cassette and 12 discs CD Changer.

Thank in advance.

Luis Arnel

[dcfish]

Maybe your amp is failing.

[Luis Arnel]

Maybe your amp is failing.

In your undertanding, it needs to be replaced? It is appart from the radio? I have no experiece with Gs in this matter.

[intakerGS]

Amp is apart from radio. I believe it's in the trunk for 1st gen. GS, under the CD player.

[1990LS400]

If your GS has one of the old dealer installed Lexus phone systems, failure of the phone ECU in the trunk can cause sudden total loss of all sound from the audio system. The phone system is integrated into the audio system including a feature that mutes the audio system sound when a phone call is in progress and sometimes also lowers the HVAC blower speed. When the phone ECU fails, it often permanently grounds the mute connection to the audio system. The solution is usually to unplug the connectors from the phone ECU in the trunk. After unplugging the connectors, if any of the unplugged connectors will plug together, then do that to complete the circuit.

I did this on a friend's 1999 LS400 a few weeks ago. Disconnecting his phone ECU restored his audio system volume instantly.

[Luis Arnel]

If your GS has one of the old dealer installed Lexus phone systems, failure of the phone ECU in the trunk can cause sudden total loss of all sound from the audio system. The phone system is integrated into the audio system including a feature that mutes the audio system sound when a phone call is in progress and sometimes also lowers the HVAC blower speed. When the phone ECU fails, it often permanently grounds the mute connection to the audio system. The solution is usually to unplug the connectors from the phone ECU in the trunk. After unplugging the connectors, if any of the unplugged connectors will plug together, then do that to complete the circuit.

I did this on a friend's 1999 LS400 a few weeks ago. Disconnecting his phone ECU restored his audio system volume instantly.

I check the whole trunk area and I didn't find any other connection than the three plugs connected to the amp. Neither a phone system. Maybe the amp is damaged. Is better to replace with a new one or repair the old? I prefer to keep all wiring with original plugging, that's an advice of well trainned electronic technician, do you agree?

[Luis Arnel]

Amp is apart from radio. I believe it's in the trunk for 1st gen. GS, under the CD player.

It was right there, thanks for the info.

[intakerGS]

Is better to replace with a new one or repair the old?

Repairing depends on the type of damage (moist/rust/other) and also how easy it is to obtain a new one. From that perspective, a repair may be far more economical. I believe mr. dcfish can advice better, as he is an expert on lexus audio equipment etc.