Connor

New Member
#1
My check engine light came on, and my transmission would not go past third gear, and I had delayed acceleration. The code "P0977" came up on the OBD reader. I disconnected the battery, reconnected it, and the car drove perfectly normal for a few days. Then, it came back on again, same code. I disconnected the battery and checked all fuses, then started the car. Now, the car shifts into all gears and drives normally, but the light is on again, now putting out code "P0788" and my stabilty control light is on. I know it's talking about the shift Solenoid A & B, is this an electronic malfunction, or is there something seriously wrong? I only ask because the car is still driving normally.
 

ZeCorolla

I Love Corolla's!
#2
Have you ever changed the transmission fluid in your car before? If not, check the dipstick and see how the condition of the fluid is.

Usually, people who never service their auto transmission fluid will result in the transmission fluid degrading and damaging the shift solenoids. I'd start by draining out all of the old fluid and replacing it with new fluid to see if it helps with the codes and shift quality.
 

Connor

New Member
#3
Have you ever changed the transmission fluid in your car before? If not, check the dipstick and see how the condition of the fluid is.

Usually, people who never service their auto transmission fluid will result in the transmission fluid degrading and damaging the shift solenoids. I'd start by draining out all of the old fluid and replacing it with new fluid to see if it helps with the codes and shift quality.
It was actually a burned out computer. I change my fluid regularly, and had just flushed it last year, but I checked that anyway. With the way the codes kept changing all the time, I figured it had to be what the solenoids talked to, and I was right. It's at the shop right now getting a new computer installed.
 
#4
It was actually a burned out computer. I change my fluid regularly, and had just flushed it last year, but I checked that anyway. With the way the codes kept changing all the time, I figured it had to be what the solenoids talked to, and I was right. It's at the shop right now getting a new computer installed.
Burned out ECU, PCM? Which computer part was the culprit? I'm fairly new to cars and their electronics so I'm wondering what was faulty so I get a better sense of what controls what.
Computers I know like the back of my hand :p
 

Connor

New Member
#5
It was the main ECM, between the engine block and fuse box. I think it failed because my car was submerged in around two to three feet of water last year, and part of the ECM was underwater. Probably shorted something out that didn't make itself known until now.
 
#6
It was the main ECM, between the engine block and fuse box. I think it failed because my car was submerged in around two to three feet of water last year, and part of the ECM was underwater. Probably shorted something out that didn't make itself known until now.
How much did it cost to replace the ecm? Im having similar issues. Thanks.
 

Connor

New Member
#7
How much did it cost to replace the ecm? Im having similar issues. Thanks.
Sorry for the late reply, haven't been on in a while. It cost me around $900 total. $140 to diagnose, $180 for two new keys as three are required to program a new ECU, around $300 for a used ECU, and then the rest was labor and tax. Not a fun payment, but it fixed the issue!
 
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