Lexus IS Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
IS 250 jerks into 1st when coming to a stop while in drive. When I put the car in neutral to stop it does not. Got the B solenoid replaced, there are no metal shavings in the transmission (which is 1 1/2 years old), the ECU unit has the latest upgrades. I bought a used ECU and it would not start, then I sent the ECU to get repaired and it did not fix the hard downshift. Car runs fine otherwise. At a loss. ANY SUGGESTIONS please.
 

·
Registered
Joined
·
152 Posts
Your complaining about a harsh downshift into first at speed. In addition, your wondering why shifting to neutral doesn't help slow down the car. Either its manual and your jamming the fuck out of the shifter through a lockout or doing it with an auto manually which equally begs the question.... Why?
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
I guess I didn't explain well enough. This is automatic transmission & when slowing to a stop it auto downshifts smooth except from 2nd to 1st...there is a jerk. Therefore I put the car in neutral when I have to slow to a stop because then it doesn't jerk as it isn't downshifting. It's been to lexus & a tranny mechanic both misdiagnosed with the repairs suggestions listed in my 1st post.
 

·
Registered
Joined
·
2 Posts
IS 250 jerks into 1st when coming to a stop while in drive. When I put the car in neutral to stop it does not. Got the B solenoid replaced, there are no metal shavings in
the transmission (which is 1 1/2 years old), the ECU unit has the latest upgrades. I bought a used ECU and it would not start, then I sent the ECU to get repaired and it did not fix the hard downshift. Car runs fine otherwise. At a loss. ANY SUGGESTIONS please.
This happened to me exactly as you describe! (hard downshift into 1st )

I own is250 MY2008, 120'000 km, RWD, automatic transmission.

about a week after this happened, the Check Engine light + Check VSC came up, i connected the obd scanner ans saw "P2714 Pressure Control Solenoid "D" Performance/Stuck Off." code.
i disconnected the battery for 10 minutes and the car drove ok again.

after a month, the P2714 error code came up again, I talked with the dealer here and asked about any Updade available for the transmission, he said to come over and check the car and connect it to Lexus-diagnostic-tools and Update the software to see if it will solve the problem.

Im planning to go to him and will let you know in any update.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #6
Any new info from anyone? All the people I talk to say sell it but how can I sell it with this issue? Having to put it in neutral every time I have to stop is a pain plus I am afraid it may eventually effect something else in the car. Lexus was no help either. Thank you
 

·
Registered
Joined
·
2 Posts
*Update*

(2nd time) The Error Code P2714 Pressure Control Solenoid "D" Performance/Stuck Off + Check VSC appeared agein 2 weeks ago, I cleared it and the car back to normal.

(3rd time) Today it happened again: P2714+Check VSC + the transmission stuck on 3rd gear and the rpm accelerated, I cleared it and the car back to normal.

(4th time) Today it happened again: P2714+P0751 Shift Solenoid "A" Performance/Stuck Off + Check VSC + the transmission stuck on 3rd gear and the rpm accelerated, I cleared it and the car back to normal.

So I went to the dealer, they did some software update to the transmission (A960E transmission), the vehicle works normally in the meantime.
They charged me for 100$ for the diagnistic+Update.
 

·
Registered
Joined
·
1 Posts
Any update since Jan? Did the software upgrade do the trick? My 07' IS350 is doing the same thing.

Thanks.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #9
Shlomie11 I am glad the update helped you. So far no help on this end. If anyone else is having the issue please let us know what your solution was if you got one. The check engine light does come on randomly and goes back off on its own. The code is bad B solenoid which was replaced a year ago when the code first came on but is keeps coming on anyway.

Recap....automatic 2006 is250 hard downshifts into 1st (all on its own) when coming to a stop. I put it in neutral right before stopping to prevent the car from jerking when it shifts into 1st. Transmission is only 2 years old, no metal shavings in it, B solenoid repalced about a year ago, was told by Lexus the computer is updated. Tried a used computer (new ones cost 3000) and it did not work so returned it. Tried a computer repair guy and it did not work so got my $ back.

There is no jamming of the gears or manually shifting, just slowly breaking for a stop light/sign etc.

THANK YOU for any info
 

·
Registered
Joined
·
1 Posts
ECU repair fixed the hard downshift

My 06 IS250 had 148K miles and I had the same hard downshift from 2nd to 1st around 8 mph. There was no change in RPMs so I thought it was electronic. I took the chance and sent the ECU out for repair and the car was back to normal when I reinstalled the ECU.
 
1 - 11 of 11 Posts
Top