2004r transmission lock up situation.

[78elk]

I started the 78 Elk again today and put it on the road. I didn't go over 45 mph due to that was the speed limit. I chose that route due to when I checked the lock up before it struggled at 25 and the rpms would drop when I flipped the switch on. This trip over 40 the rpms didn't drop and it didn't stumble at 20 mph like it did before. The cruise control worked great at 25, 35 and 45 mph. They are on the same fuse. Any ideas of what is going on?

 

[78elk]

Any ideas of what I need to check to diagnose the problem with the torque converter lockup that did work until I installed the cruise control. The only thing the 2 devices share in common is the fuse.

 

[melloelky]

so the cruise(which works) and lock up are powered from the same source,have you check to see if there's any power @the trans? i.e the other end of the circuit.

 

[78elk]

Thank you. I haven't had the time to get to it. Hopefully Monday and Tuesday I'll get a chance.

 

[78elk]

A second thought maybe it's staying locked up. How would I know if that is happening?

 

[78elk]

I want to let you know what has happened on this transmission. I installed it in 2019. The torque converter lockup worked great. The cruise control was installed in 2020. The torque converter lockup wasn't checked after that. Then I had trouble with the speedometer after that
The first time I checked the torque converter lockup was in August of this year. So I'll have to see what changed with it so it doesn't work.

 

[78elk]

What is the proper way to test the wiring from the transmission to the toggle switch and the fuse.

 

[78elk]

The wires are plugged into the accessory 30 amp fuse. The fuse a connection s are fine, no problem there.

 

[78elk]

I'm having some problems checking this out. I have a 2 pole toggle switch. 1 wire goes to the fuse panel and the other goes to the transmission.i get a voltage reading of 11.5 volts when the switch is off. When I switch the wires it reads the same 11.5 volts when the switch is off. It reads 0 when the switch is on.

 

[78elk]

I took the voltage meter and checked each screw with the voltage meter. One lead to the dash ground and the other on one of the screws on the switch. I got a reading of 10.9 volts on both screws with the switch on and 10.9 volts only on one screw when the switch is off. So the switch is working properly. My problem was I didn't realize that I needed to use a ground when testing it.