Dealer Advised Me Against Disconnecting Battery...

[NC_lexus]

on my 92 LS400.

My motive would be to clear the codes that i suspect are causing the TRAC ligt to come on randomly.

will the radio have to be reset?

anything else?

[TexasLexus94]

Whether the radio will have to be reset is an open question. It has been discussed here many times. It's best that you know your code prior to disconnecting the battery. Some members have said that they have disconnected the battery, and did not lose the radio.

If you do lose the radio, and don't know the code, try inputting the last 3 numbers of your VIN. It worked for me.

[wwest]

Flush the brake system but be sure the bleed valves at the ABS pumpmotor assembly and the accumulators are opened along with the ones at the calipers.

If you notice its the tenth application of the brake after a start that turns the trac light on.

[SKperformance]

don't clear the code get it read ,find out what it wrong and fix it.

otherwise go to autozone napa or another parts store to read the code and clear it for free

[UCF3]

Definitely find out what codes are being scanned.

You may find this information useful.

http://uktoyotaestimasite.tripod.com/obdcodes.htm#obtaincode

[KY350]

Can you advise if you are also getting the orange engine light on together with the trac light?

This is happening in my 91 model and my mechanic has diagnosed no. 51 and 55 error codes. These codes are interrelated and I need to change the knock sensor to stop the lights from coming on in the dash. Quote for repair is approx $500 - $600 Australian. As my trac light only comes on intermittently (once a week) and it can be overcome by simply switching off the engine and restarting while at a set of traffic lights, I will not get it fixed, as the manifold must be removed to access the knock sensor which is located in the bottom end of the V configuration of the engine.

BTW, Lexus wanted to charge the previous ower $2,500 to correct the trac light!!!!!!

[SKperformance]

A knock sensor rarely goes bad , you probably have a real bad set of carbon build up in the engine.

I don;t know if they have motorvacs down their but i would try and find a shop to do that for you