P0762 transmission issues
 

Hello,
I have a Mazda 3 2005 2.3L automatic and the AT light recently came on. The OBD code is flashing a p0762, shift solenoid C stuck on. When driving, at about 50mph the car will start to shake while attempting to shift into 3rd gear but is never able to shift while the rpm's are going up like crazy. Also, when I reverse the car makes a clunking noise and jerks back and also had some slippage way back. I've already had an ATF flush, replaced the shift solenoid C, replaced all spark plugs, and checked the motor mounts. I'm running out of ideas now. When tranny pan was taken out there was no debris present. I was thinking that it could be the tcm but I've been trying to look it up for the 2005 and nothing, so now i'm starting to think it doesn't have one. My next guesses are the ECU, speed sensor, pulse generator, axle, coil pack, and the valve body. Any thoughts? I appreciate any and all help.

Have you had a line pressure test carried out? ( Transmission fluid pressure at various conditions)

I have a 2005 Mazda 3 S automatic (103,000 miles) and the AT light (following a tranny slip) has been coming on during start ups or warm ups. I turn off car and restart and AT goes away. It has been going on for 13 month but has apparently not worsened. Several repair shops have refuse to even look. No code reads possible. I have siphoned put some of old fluid and replace with good fluid and Lucas additive. Adding a fresh quart that way actually makes the slips and AT go away for a few weeks, then it returns. Fluid level is OK. I have had a lot of luck by simply leaving car in neutral for a minute, then driving it slowly for a while. It takes longer to warm in winter. Any ideas? Will a filter change or flush help? Fluid is very clean from siphoning on multiple occasions.

How you fix your car
 

i have same promblem with you.. can you share how you fix your car?