JCHO

I have 99 GS4 and getting P0770 error code.

I have talked with 2 mechanic friends and it sounds like a problem with a speed sensor in the tranny (GS4 has 3 or so sensors). I also mentioned to them that I have PI TC and they both said I would probably need to check with a dealer see if there is an updated software for the car since I am not having any problems with my tranny (shifting, ride, sound..)??

I was wondering if anyone have this problem before and how did you fix the problem?
How much did it cost to fix the problem (which worries me if I could only get this done through Lexus dealer per Mo at SRT )?

Thanks in advance.

koolaidman

id take it to the deal on my side it says shift sol e malfuntion. could be a number of things torque converter lock up(replace tc), slu soliniod, valve body,

kpuri

Just incase you are a DIYer see attached PDF for P0770
(You may have to right click and save as)

TLW

search that code on here

sometrhing like the TC upgrade and that CEL light go hand in hand

JCHO

Thanks Kpuri.
I am mechanically challenged but I will definitely have my mechanic friend take a look at it.
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So far, it looks like no one is familiar with a software update.

I did the search for this error prior to my post and they all seemed to indicate shift solinoid or sorts. Which I turned around and told my friend about. That's where the topic about software came up. Mechanic friend said I would probably need a software update for my car and then about week later, I told another mechanic (who used to work at Pohanka Lexus here in Virginia) about the error code. He asked if I noticed any problems with the drive, shift, etc.. When I said no, he said to take it in and mostly likely need a software upgrade.

I will talk with my mechanic friend again since he does everything I need for my car.

Thanks everyone and I will update as to the outcome on the fix.

JacobT

I'm very familiar with the P0770 code.It's the PI TC that triggered the code. I had dealer replaced all 3 solinoids but the CEL and error code were still there. There's no software update will fix this problem. The only solution is to swap back the stock TC. Or you can try to reset the ECU every 300 miles when the CEL comes on.

Trust me, I have been searching answers for this problem for the last 4 years

JCHO

Thanks Jacob T. I was afraid of that....... this sux!.

koolaidman

lol @ u ppl look what i said