Shift interchange solenoid?

Andy663 · November 11, 2021

Hi, My EML came on, my local garage says it's the shift interchange solenoid. Does anyone know what this is and is it expensive to fix? I have a 2005 GS300 (Phase 3). thanks.

GS3UK · January 4, 2022

It will be an expensive job !

Any update on this ?

Ive been having the same issue , error was shift solenoid C and so i first did a drain and refill of the gearbox fluid and this did not cure it after which i had it booked in with a gearbox specialist who advised that changing the solenoid may not cure or may just cure it for a while this was because there was a lot of metal shavings in the drain pan and so i took the risk of changing the solenoid anyway

After doing this the garage have said that the fault is still there ! and that it is from the actual moving parts and so a full strip is needed to see what the fault is ...

So its either that or a used gearbox if wanting to keep the car

OJWM · January 10, 2022

On 1/4/2022 at 5:24 PM, GS3UK said:

It will be an expensive job !

Any update on this ?

Ive been having the same issue , error was shift solenoid C and so i first did a drain and refill of the gearbox fluid and this did not cure it after which i had it booked in with a gearbox specialist who advised that changing the solenoid may not cure or may just cure it for a while this was because there was a lot of metal shavings in the drain pan and so i took the risk of changing the solenoid anyway

After doing this the garage have said that the fault is still there ! and that it is from the actual moving parts and so a full strip is needed to see what the fault is ...

So its either that or a used gearbox if wanting to keep the car

I've got the same issue (code being thrown for Shift Solenoid C). Car currently in with Lexus (for second time, given I stupidly cleared the codes ahead of the first time). Will see how many zillions of pounds they tell me it'll be to fix.

How does your issue manifest itself? My '08 GS300 drives perfectly, apart from behaving like it's in a high gear just after starting up when cold. That clears up within a minute or two, then it drives normally.

GS3UK · January 11, 2022

My car drives and idles perfectly , however it will not engage gears 4,5 and 6. Smooth changes from 1, 2 and 3 and that's it ! so limited to 35ish mph

Error codes suggesting shift solenoid C , had this changed and refilled twice of fluid but still the same issue . No longer shift solenoid error code

Was advised to swap gearbox but after reading many forums it seems it could be faulty ECU and so im in the process of trying this before either swapping the gearbox or something else more costly

OJWM · January 11, 2022

3 minutes ago, GS3UK said:

My car drives and idles perfectly , however it will not engage gears 4,5 and 6. Smooth changes from 1, 2 and 3 and that's it ! so limited to 35ish mph

Error codes suggesting shift solenoid C , had this changed and refilled twice of fluid but still the same issue . No longer shift solenoid error code

Was advised to swap gearbox but after reading many forums it seems it could be faulty ECU and so im in the process of trying this before either swapping the gearbox or something else more costly

If all else fails, move to London - you won't be able to get anywhere near 35mph regardless 😉

Got an update from Lexus dealer slightly earlier - they've advised that my solenoid issue (though code reports it as being solenoid C) is actually with an S3 solenoid... Not that I'm sure what difference that makes. Hopefully it'll be cheaper to remedy, but I somehow doubt it...

Best of luck with your issue!

Linas.P · January 11, 2022

If you have metal shavings in the pan then replacement gearbox is most likely. The only other option would be full rebuild, but I was not able to find any place in London which would still do that. Seems specialists doing that sort of work have gone extinct in UK. Besides I guess rebuild in UK would cost more than good used gearbox.

However, if you just have solenoid performance issue, it could be that AFT and filter replacement could do a trick. My experience is from IS250, but gearboxes are very similar in GS300 (a960e vs a760e). In my case gears were hanging on overrun and I would get VCS light and Solenoid A or C performance code. Driving normally it would not occur, only when I floor the car and instead of changing just before rev limiter it would go all the way and hit the limiter and stay there and would not change unless I would lift for a second before changing.

Note car had nearly 200k miles on the clock and AFT was not touched for at least 120k, fluid was dirty, but there was nothing unexpected in the pan. AFT and filter change cured the issue. In case it wouldn't work I would have gone for set of solenoids, there was generic set sold at eBay for ~£140 at the time (genuine ones are ~£800, rendering replacement not economically viable at that point). However again - if you have any foreign object or probably worse - metal pieces, then I tend to believe it is ruined and not worth fixing.

GS3UK · January 15, 2022

So i did the ecu swap and this did not resolve the issue and so it is looking like i will have to have the gearbox replaced !

It is the A960E and part number should be 35010 - 30B60, however i am being offered part number 35010 - 30B20. I cannot see anywhere what the difference is or if it is an A960E at all ?

Ted Soudan · February 11, 2022

On 1/10/2022 at 6:17 PM, OJWM said:

I've got the same issue (code being thrown for Shift Solenoid C). Car currently in with Lexus (for second time, given I stupidly cleared the codes ahead of the first time). Will see how many zillions of pounds they tell me it'll be to fix.

How does your issue manifest itself? My '08 GS300 drives perfectly, apart from behaving like it's in a high gear just after starting up when cold. That clears up within a minute or two, then it drives normally.

Answer:- Code is P0763 Solenoid C Electrical. I swopped all transmission oil with a full flush, filter replacement and reccommewndation that I drive for 80 miles plus in the hope the it will 'RE-SET' itself. No such luck. However, replacing the solenoid is NOT a' gearbox out' solution but can be replaced in-situ. My Lexus still drive PERFECTLY in every respect (Normal, Power and Snow mode), so much so that I am wondering whether I have a simple (albeit 'dash out) electrical wiring fault to the switch. Will keep you posted.