98sleeper

98 GS 300 was going into limp mode - only 20% throttle. I could turn it off and restart it and it would run for about 30 min of driving and then go into limp mode again. Thought it was the Accelerator Pedal Position Sensor. Took it off and cleaned it - popped the top open and cleaned all contacts but it didn't seem that bad. Re assembled, re-calibrated then BAM!!! Alarm goes off, all lights flash and blink, the ac ducts flap, the cd player hunts for cd's and it won't stop until i turn it off and turn it on again or put the key in the door and unlock the car. The car won't start, it only clicks rapidly as though the anti-theft function is active.

I thought it was the battery, but i charged and checked it and it's 100% charged. What gives???!!!

98sleeper

It was throwing the codes p1120 and p1121.

GS3KID

hello, you need this!


http://www.ebay.com/itm/LEXUS-TOYOTA...VViuwF&vxp=mtr




heres a thread with info on your issues.


https://www.clublexus.com/forums/per...-problems.html

98sleeper

Not sure if that will fix the non-start issue and the alarm and anti-theft going crazy tho....

GS3KID

did you disconnect the battery? I've had a similar incident when i replaced my door lock actuators, when i reconnected the wiring harness without disconnecting the battery my car had some of the same issues pluss all the windows rolling up and down multiple times. maybe you blew a fuse?


I know older Lexus models like the SC's anti theft reset when stick the key in the driver door and unlock 2x quickly but idk about our GS's

99 GS3

iTrader: (14)

The immobilizer function of the GS wouldn't do that, the immobilizer still allows the car to crank but it will never fire up.

98sleeper

Thanks Lexus Family! It was a weak battery AND the immobilizer. Got it to recognize the key and charged the battery. Good as new!

burteboy

Did you perform any repairs lately? It looks like you have a loose orbad ground problem. . Check all yor engine and chassis ground.