Torque converter clutch

we it can be more than one cause.
bad TC (slips too much locked )
bad TC solenoid on TC or pump.
bad TCC relay(if present)
or bad PCM/TCM
the service manual covers all this, pay them like I must do too.
the problem is both electrical or pure hydraulics

https://eautorepair.net/Marketing/Default.asp

code p 0740 refers to the torque converter clutch (TCC) solenoid---circuit malfunction====causes ---wiring---TCC solenoid---ECM/TCM ( transmission control module )
at this point I would consider changing the TCC ( check the harness connections and wiring first)
the price can vary as to where you get it from or even if you need a new one as the unit from the wreckers or junk yard may be just as good
ring around service center spares, specialist transmission shops to get prices

P1860 All GM - TCC (transmission Torque Converter Clutch) PWM Solenoid Circuit Electrical.
P1860 Description The Torque Converter Clutch Pulse Width Modulation (TCC PWM) solenoid valve controls the fluid acting on the converter clutch valve. The converter clutch valve controls the TCC application and release. The solenoid attaches to the control valve body within the transmission. The solenoid receives ignition voltage through circuit 239. The Powertrain Control Module (PCM) controls the solenoid by providing a ground path on circuit 418. Current flows through the solenoid coil according to the duty cycle (percentage of ON and OFF time). The TCC PWM solenoid valve provides a smooth engagement of the torque converter clutch by operating during a duty cycle percent of ON time.
When is the code detected? When the PCM detects a continuous open, short to ground or short to power in the TCC PWM solenoid valve circuit, then DTC P1860 sets. DTC P1860 is a type B DTC.

Possible causes - Faulty Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid
- Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid harness is open or shorted
- Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid circuit poor electrical connection. Unless you have a factory manual and very good auto repair skills this is best left to an expert. It is a messy dirty job that requires removing the parts inside the transmission for testing..

you need a better mechanic that traces ALL of the possibilities of each code, not just read the code and trow in a part hoping that it's fixed ~ it can be wiring as well, not just plug in a new part as mentioned on the 2nd trouble code to the vehicle speed sensor

P0744 Torque Converter Clutch Circuit Intermittent


P0722 Output Speed Sensor No Signal

the first of the 2 looks to be more intensive to trace and find out the problem & the 0722 is the easier job for an intermediate mechanic to trace the wiring for continuity

code p0740 refers to torque converter clutch (TCC) solenoid --circuit malfunction===causes--- wiring --TCC solenoid--- ECM/TCM

code po740 refers to torque converter clutch(TCC) solenoid--circuit malfunction===causes--wiring--TCC solenoid--ECM/TCM Replace the TCM ( transmission control module) as it controls the clutch and the OD servo.

code po740 refers to torque converter clutch(TCC) solenoid-circuit malfunction==causes --wiring--TCC solenoid-ECM/TCM
code p0343 refers to cam shaft position sensor(CMP) A bank1-high input.==causes --wiring short to positive--CMP sensor---ECM. check which cam sensor you replaced and check the wiring connectors. use a code reader to reset the cpu when finished

That is located in the transmission and can be very expensive to repair/replace - Do NOT take to Amco! Did he also tell you the exact electronic code? Uusally, the code will say more than just torque converter.

Have you noticed any hesitation when you are starting to move; in reverse on on a hill - any noticeable slipping?

My 2007 code book says Torque Converter Clutch Solenoid Circuit open.

Go to autozone & have them do free scan & interpret code.