Car won't rev over 2500rpm, "Shift Solenoid E Malfunction"

Maintenance/Repairs
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1

Hey all! I have a 2003 Toyota Corolla. A couple days ago, the check engine light came on out of nowhere. Plugged in my diagnostic tool, it gave me code P0770, which is “Shift Solenoid E Malfunction”. Made an appointment with a transmission specialist for a few days later, but after about two days, the check engine light went off. The mechanic suggested that I not bring it in, and instead wait for the light to come back on.

But now the car won’t rev over 2500rpm (while driving). It’s not stuttering, and I can get up to 70mph just fine, it just takes longer than normal.

My main questions are:

  1. Is this symptomatic of a solenoid malfunction? Why or why not? I’m curious as to if I have two problems, or just one.
  2. In your opinion, is the car “safe” to drive until I can get it fixed?
2

The first thing I’m going to ask is, when was the last time the transmission fluid was serviced?

If you don’t know or can’t remember, that’s where I’d start.

Tester

3

Probably never. I bought the car about a year ago, and I’m almost sure the previous owner didn’t. I’ll get that checked out, thanks.

4

With vehicle in neutral will it rev past 2500 ? Just a blip of the throttle to try and pass 2500 is all you need. If it does then transmission problem if it doesn’t then something else.

5

Just tried it, got up to about 4000rpm, wasn’t comfortable trying to rev past that in neutral as it was fairly loud.

6

The computer has a rev-limiter.

It won’t allow the engine to rev past a certain RPM while in neutral to prevent damage to the engine.

Tester

7

Nice! So definitely a transmission issue, I’m assuming.

8

Just enter “DTC P0770” into your search engine, and you’ll see what can cause this code.

One of the first things mentioned is dirty transmission fluid.

Tester

9

Yeah, I did that. I was mostly just curious as to whether the dirty transmission fluid would directly limit my RPMs, or whether this was two issues manifesting simultaneously.

10

I’m looking in the service manual and I don’t see P0770 applying to this car. There is no shift solenoid “E” in this transmission. Is this a 2004 Corolla?

11

To be honest, I constantly forget whether this car is an '04 or an '03 without getting out the paperwork, but it looks like it’s an '03 since it gave me the P0770 code. Thanks for pointing that out, I’ll update the OP.

12

Let me explain this to you as simply as possible.

The computer has seen a fault within the transmission.

The computer has set a code to let you know there’s a problem within the transmission.

The computer will then set the limits on how the engine/transmission operate to prevent damage to the transmission.

This is called the, LIMP MODE

This means the vehicle will operate under these conditions until it’s figured out what’s causing the P0770 code.

Tester

13

Thanks for the summary, pretty much answers all of my questions. Thanks to everyone else who participated as well!

14

On the 2003 Corolla P0770 is set if the torque converter clutch fails to lock, that’s bad news. The diagnostic test starts with testing the solenoid but that usually isn’t the problem.

BTW, you said the check engine light went out, why should the vehicle be in limp-in mode?

15

Wow you’re right, I was just reading about that! Good point about the limp-in mode as well. I really need to get it to a technician ASAP.

16

It sound like the transmission might be stuck in high gear, is it shifting? Might be just a matter of time before faults are set.

17

I can’t really tell if it’s shifting or not anymore. Whenever the car needs to accelerates, it goes from 2500rpm to 2000rpm, accelerates a bit while going back to 2500rpm, then decreases to 2000rpm again to accelerate some more. There’s no audible difference if it’s shifting at all.

18

Have you looked at color of the tranny fluid?

Is it bright red? Or the color of used engine oil?

Tester

19

I’ll have to check it in the morning, it’s pitch black out here, I can’t really tell. But if it is bright red, what’s your diagnosis?