Warning Lights

ruds · February 20, 2005

GS 300 SE 1998

While I was out driving the other day doing a steady 40mph, the throttle pressure appeared to go strange - as if power reducing. Then all power seemed to fade. The VSC, VSC OFF and Engine Lights all came on. In flowing traffic so I had to quickly switch off and back again so I could note down the warning system. Pressing the gas did nothing as revs dropped. I turned ignition off and then back on and then all was fine. Slightly confused I thought little of it.

Now again today the same thing happened although this time I had just slowed down to about 10mph. Again power dropped and all three lights came on. I left the engine switched on while I noted down the events.

Looking in the owners manual it appears to be something to do with the Vehicle Stability Control System or Traction Control System.

Has anyone experienced the same thing and what can I expect to be the root cause??

All help appreciated

Thanks

ColinBarber · February 20, 2005

Sounds like the electronic throttle shut down. You need to press the accelerator down all the way to get any response.

You need to get the stored error codes from the ECU otherwise we are just guessing what the cause is. Either take it to a Lexus dealer or somebody with an OBD-II reader to get the codes.

Dave M · February 24, 2005

There was a recall on the yaw rate sensor for '98 GS300s - they weren't properly electrically shielded and could be upset by electrical noise.

Apparently it was a problem if people kept a mobile phone in the center armrest.

Might be worth checking that your car's had the mod. I was told the symptoms would be the system reducing power and possibly applying brakes on one side.

ruds · March 1, 2005

Update: Took car to local dealer. They put it on diagnostic machine and it returned as all clear. They did however detect the 'problem' that occured as they were able to tel approx time and car speed (which was interesting). Any way it returned all clear. They did say though that if it happened again th it would indicate a faulty Throttle Sensor - which would need replacing £350.....

Told me to take it away and monitor.

A little pi**ed to be honest, just had timing belt and brakes done a week before. £££££ and now this.

Guess what it's just happenned again, town driving and slowly the pressure in the throttle reduces until it just goes altogether and the warning lights come on.

Going on the recall Dave mentioned. Does anyone have any further info on this as maybe I could get this replaced as a recall job and not have to fork out.

Dave M · March 2, 2005

I think Lexus would do the Yaw Rate sensor repair for free as it's a safety issue although it's pretty likely it's already been done I would imagine.

It does sound as if it's the electronic throttle shutting down (there's a physical cable connected to the throttle as a backup fortunately). It's interesting you said that you'd just had the cambelt replaced as they'd have had to disconnect the wiring harness from the throttle body to do that.

It might be worth checking the plugs to the throttle motor / sensor etc. are all seated properly and maybe clean the contacts up, just incase some dirt in there or something's loose.

Hope you get it sorted without having to inject too much cash!