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P2761 No lockup, help.

Old 12-17-2014, 11:40 PM
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Default P2761 No lockup, help.

Hey guys, I'm having an issue with my 2004 1500 5.3 4l60e. The transmission was built two years ago and has a new yank ss3600. I went on a two hour drive today, all highway, to pick up a 6.0. On the way to my destination my truck drove great, shifted fine and the converter locked fine. On the way back, right off the bat, I immediately got a CEL and the converter would NOT lockup at all. The code was P2761. I had no choice but to drive 2 hours back home, with no lockup, cruising in 4th at 65 turning 2500 RPM's. I had to stop roughly every 30 minutes and restart, from a dead stop because my truck would start losing speed and would require even more throttle to maintain a constant 65. The research I did points towards the ignition switch, but I am not having the limp mode symptoms everyone seemed to have with the ignition switch being the problem. The truck runs through the gears fine, the converter just doesn't lock up. When I got home I checked the transmission fluid and it was a tan color and smelled burnt. I will be pulling the pan tomorrow to see if I can find anything. Any help is greatly appreciated.

Thanks guys,

Erik
Old 12-18-2014, 12:51 PM
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Old 12-20-2014, 12:07 AM
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P2761 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 the OFF/ON/CRANK voltage circuit. The Powertrain Control Module (PCM) controls the solenoid by providing a ground path on the TCC PWM solenoid valve control circuit. 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 TCC by operating during a duty cycle percent of ON time.

When is the code detected?
The Powertrain Control Module (PCM) commanded the Torque Converter Clutch Pulse Width Modulation (TCC PWM) solenoid on and off and the feedback voltage was out of range

Possible causes
- Faulty Control Solenoid Valve Assembly
- Control Solenoid Valve Assembly harness is open or shorted
- Control Solenoid Valve Assembly circuit poor electrical connection
Old 12-21-2014, 12:23 AM
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Why didn't you just drive with it in third where the rpm's wouldn't have dropped below stall speed? More gas, but you would have kept the trans temp cooler.

Solenoid and connection would be my first places to start.

Then I would do a fluid flush, especially as you said it smells burnt.
Old 12-21-2014, 01:24 AM
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Most likely insufficient line pressure for some reason leading to clutches wearing rapidly. The code you have is probably the tip of the iceberg considering your fluid is tan (clutch material) and burnt smelling. I'm guessing you don't have a trans temp gauge as the every 30 minute thing is going to be slipping clutches and very hot fluid.
Old 12-21-2014, 08:41 PM
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Hey guys, got the transmission pulled and the torque converter was destroyed internally. Metal shavings everywhere. I'm guessing it blew and sent metal throughout the transmission which clogged the solenoids. I do have a trans temp gauge. It never went over 200*, but 190* for two straight hours is probably pretty bad for the transmission.
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