2005 toyota prius hybrid transmission issues

Car has 180000-k miles–well cared for–runs --drives ok but after 10 minutes if you come to a stop there is no power or same if on the highway at cruise speed–slows way down to like 35 mph–also if you are traveling at 35 mph its will go on to cruise control aotomatically. This is my first prius–it does have a service engine light on the dashboard

Is the service engine light on the dashboard lit? blinking?

In a Prius you really can’t pinpoint the problem on the transmission. You have a problem with the electric motor/gas motor synchronization system. The involves a computer controlling the process, sensors, mechanical, and electrical parts. It is much more complicated that a simple transmission problem in a conventional car. I’d say your only option is to take it to a Toyota dealer. The dealer is the only place with the diagnostic equipment needed to service a Prius in this case.

Turbo is correct. A Prius specialist is the only option…

I agree with Turbo and Caddyman. Also have you had the transfer case oil changed at all? It should be changed every 100,000 US miles. If that oil is starting to age, it could be coking (Carbon deposits) on the sensors adding to your issues.

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Thank you everyone for response !
its off to the dealer


Sounds to me like the small auxiliary battery may be dying. Low voltage to the computer causes all kinds of strange behavior, and my car acted similar to your description when it died. Car suddenly went to a crawl, and would stay on only briefly. I was able to use EV power alone to get off the road and call a tow truck.

Also have you had the transfer case oil changed at all?

Transfer case on a Prius??? Huh???

I think ‘transfer case’ is ‘planetary gearbox’. It transfers power between the gas engine and the two motor/generators, so it is a ‘transfer case’, in a way.

That makes sense. Never heard of the term used outside of 4wd system.

Dealer recommends flush transmission for Prius every 60k miiles.

You can drain and fill yourself without flush you can pump the fluid in until it starts to come out the top fill hole.but will only get about 1/2 to 2/3 of the transmission fluid replaced.

but you can just do it 1 2 or 3 times.to buy time. make sure your car is level when you do this.
It doesn’t have a filter only a screen my dealer doesn’t even clean it like they could or should.