paulwall86

91 LS400

So i started driving my car the other day, it was raining pretty hard. All of a sudden my car just stopped shifting correctly, and the overdrive light came on and started flashing. I had my transmission rebuilt 2 years ago. I took it back to the shop and he said it probably wasnt the transmission but electrical and said it could be a speed sensor or the wiring harness he pulled codes 63 and 67. When driving the car it shifts beautifully but about a half hour of driving it starts shifting when it shouldnt. Any ideas? Thanks

SkulCracka

trans fluid change. solinoids are sticking maybe? checking wiring first though. http://www.lexls.com/tutorials/trans...ransflush.html

steve2006

Codes are as below.
I would have a look under the car and check the wiring and plug/sockets to the transmission, perhaps water has got into them or damaged them.

63 - Open or short circuit in no. 2 solenoid valve



67 - OD direct clutch speed sensor signal malfunction

paulwall86

Does anyone know where to get a no.2 solenoid for a 91 ls400 transmission. Are there any tutorials out there that show how you replace it?

Kidrock

Hey I just had the same issue with my LS400 (1991) and took it to a local mechanic. he charged me 3 hours labor and $300 material (Toyota Tranny fluid and Solenoid kit) the car now drives perfect.

Also, I re-searched a lot and found this tutorial if you want to do it yourself...GOOD LUCK

https://www.clublexus.com/forums/per...placement.html

DietrichB

About two years ago I drove through heavy rain and DEEP puddles. Soon after, my cruise control stopped working and so did my speedo, if I remember right (not the illumination, the needle wouldn;t move) After driving a few months, the speedo started working again, then the cruise came back.
But then that next winter it started shifting improperly. Sometimes when driving away from a stop the tran would shift from first right to fourth, I think, which would immediately kill the motor. I could avoid it by shiftng up manualy. My mecahnic and I did the trans flush thing two quarts at a time, and before refilling the last two quarts, I took the pan off, and took out the solenoids which were easily accessible. I checked each for electrical operation and cleaned them. I also unplugged a connction to the trans which you will find outside the trans on the passenger side, cleaned it a little and reconnected it.
After this shifting was back to normal. Maybe the deep water disturbed that connection, or maybe one of the vehicle speed sensors (cruise and speedo), or both, I don't know.The solenoids all seemed to work fine. Shifts fine now without replacing anything but fluid.