I've got a 98 GS400 which started acting up by putting the hazards on by itself. I thought it might be the flasher, only then random things started going wrong. Sometimes the dash lights work, the ECT doesn't respond, only driver window works, no outside temperature, dome light doesn't recognize door open, random warning lights. The worst part is some will work with key in run position, but when the car is running some will come and some go. Its always different. I replaced driver fuse panel ECU because all symptoms seemed to run through it. It just made it worse. The Ecu was from another gs400 and not programmed to my car. So I'm leaning to bad main ECU. Correct me if I'm wrong, but in the 98 GS400 there is no gateway ECU only the main ECU. The car runs great, I'm only having interior functions going crazy. If there is gremlins in this world I believe some moved in?!?

 

My car used to do the craziest things when I bought it, all of my dash lights would intermittently flash off and on all night with the key OUT, and my headlights would turn on by themselves and the alarm would go off when it wanted too, usually at 4 am , the car would not respond to the gas pedal even when flooring it I went about 3 mph, I thought I got burnt and bought a lemon with a ton of gremlins and was told to sell ASAP, long story short I replaced the battery and voila ALL problems solved! These cars can act pretty goofy with a bad battery, I don't care if a reader tells u yours is good, at least get a new battery and give it a chance, it saved my butt at least and hopefully yours....

Good luck

 

Also many times this is caused by a bad ground....




somewhere

 

I bought a new battery( hazzards destroyed old one), and I'm going to start the great ground hunt. Thankx for the replies. I'll post when I find Where Gizmo is hiding in my car.

 

Put the new battery on a charger overnight especially if you only use your car on short trips

 

Whats the most recent thing you installed or repaired (inside)? It could be as simple as a screw catching a wire when putting things back together. Seen it many times start there

 

bad ground could also possibly be it too. but yeah def check the battery!

 

24 hours on the microprocessor controlled charger and still not ready. I took the battery back, and the "gentleman" behind the counter put his little voltmeter on it and said"nope its ok". After a pleasent disscussion and some none stop eye contact. He went to the shelf, grabbed a new battery, and placed the little new cap from their battery to mine and put mine back on the shelf. I explained the bad cell, but the "gentleman" had no concern. New battery installed--Yippie-- all systems right on point. I'm still going over as many grounds as possible. So far .6ohms-.8ohms on everyone. I'm still going to clean and inspect everyone I can get my hands. I promised myself this will be a blown 400hp kid hauler before I send it away. Thank you for your input from everyone. I'm going to update after letting the car run to see if there is still an underlying issue.

 

So you are saying that they are going to resell the bad battery? What store is this?

 

advanced auto

 

My 2002 SC430 ran fine after the Brake and ABS light came on. I was told I need a new Gateway
ECU. I thought I had a brake problem. What should this cost ?