It has been so long I forgot about them bolting the solenoid to the pump housing. No way to check that without trans removal. As long as you can access the wires you could apply 12V to them and see if you get a decent click as the solenoid activates. As far as the pressure switch goes I believe both those tabs are tied together. Since you only have one wire going to it the switch grounds the wire to the transmission body when it hits the correct pressure. Maybe it takes too much pressure to activate it now? They used different pressures for different MPH lockup. As long as the wire is still intact I've fixed the cracked insulation by wrapping some electrical tape, or better yet a small piece of heat shrink(split open), and then use a ty-rap or two on it to keep it from un-wrapping. Keeps the wire from touching anything. At this point I'd just take it on the chin and forget about the lock-up happening. Unless you are doing a lot of highway driving it won't make much of a difference in MPG.
Thanks No Lift. I've just hooked up a battery to the two wire terminals that lead off to the solenoid. I can hear the solenoid click on as connected and it does sound strong- and it doesn't 'relax' off until I let go of the wire on the battery/terminal. It's not conclusive, but I hear it working under zero load application, and as mentioned- stayed active for the time I had it connected to battery. I also rechecked the 46psi labelled switch. Continuity is indeed through the case to the main car body earth. So- pressure tested that again and I get a reading between either terminal and the switch case. I only got the compressor up to 50psi and the switch was activating with that. Curious I am indeed whether I should remove the transmission as you mention and check visually, or just forget. I do most of my mileage on the motorway it is true, and it does save maybe 2-3mpg (imperial) on those long trips. 200/300rpm doesn't seem like much but it does add up. I don't think now I can test anything else without removal now of the gearbox, other than the single wire itself- now that the oil pan is removed. https://www.fuelly.com/car/buick/lesabre/1980/blurredman/419446 The only thing more I can think of (i'm editing this in retrospect) is to double check the loom wire coming down- it could be that continuity is not made at specific bends/placement of the wire. Intermittent connection internally at a bend perhaps. I can easily check this by turning the ignition of the car on and connecting touching wire to governor to any earth and I should hear the solenoid click on. Then wobble and flex the wire from the loom.
I get continuity but not voltage from the line that leads to the transmission. Assuming there is a switch/relay under the dash somewhere as that's where the single wire leads after / before the wire goes to fuse box. It's a bit difficult for me to get under there are the minute. Have double checked brake switch. One contact is current continually, the other is current only when the pedal is depressed so that seems fine too. Trying to find a wiring diagramme.
Could you wire in a backup circuit and connect that to a toggle switch? Reassemble and drive it, see if you can duplicate the non-lock behavior, then flip the toggle to see if the problem lies in the circuit or the solenoid…Patrick (I know some of the Turbo Regal guys use a toggle to control their lockups).
Interesting you should say that- I actually already have a toggle switch to be able to turn off the lockup when required (I live in a hilly environment and they can be a bit much for the lockup). I assumed that a constant 12v goes through the feed down to the transmission (in my case to the cabin first to the switch and back out)- if so, it doesn't now- I could indeed programme the above as you say pbr400, putting 12v ignition feed to in the least check that the transmission itself isn't the issue and it would be a good starting point. Eventually though I would prefer it to be auto or off as it used to be, and not completely manual- unless that is a last resort.
Yes, but he said that the wire is brittle and it cracked/broke when he removed the switch. He will have to replace it, but it's not the problem.
Is this car, or has it ever been a Computer Command Control vehicle? GM started the CCC system in the 1980 1/2 model year. If it is, the ECM controls the ground to the TCC solenoid by monitoring the vehicle speed sensor, throttle position sensor, coolant sensor and manifold absolute pressure sensor. If it isn't a CCC car, there is a vacuum switch that monitors engine load to know when to apply the TCC. It's very similar to what they used in their diesel powered vehicles. In the non CCC vehicles, it would send power, or ground to the TCC solenoid when the vacuum switch closed, third gear pressure switch was closed, and brake switch closed.
By the picture, he took, it sure looks like the T-200C. Has an integral tail shaft. Smaller pan, with "METRIC" embossed on the bottom. They did have a corner "cut off" like the T-350. Am guessing the T-200's were installed in B/C bodies behind the V-6's and a handful of low displacement V-8's (Chevy 267/305, Olds 260/307, Pontiac 301).
Alright, so i've finally had a bit of time to look at this and I made quick rig up of a single wire leading from the single wire plug type attached to the transmission up to a manual over-ride switch that I installed about 8 years back (the lockup trying to engage in the hilly areas of where I live was really annoying so I used to flick the switch off from essentially 'auto' until the hills were over). And the other side of the switch I temporarily directed to the battery positive with an inline 10amp fuse. And, I quickly tested the position in either direction with engine off and the fuse never blew. After getting the car to the requirements: up to temperature, and 40mph + , flicking the switch just blew the fuse. I think I'm doing the test right and ultimately I don't think (unless someone can inform me of a circuit otherwise) I can do anything more unless I dropped the transmission to inspect the lockup solenoid. That isn't going to happen. I would have liked the ability to lock up manually (when I remembered to turn it on on the motorway, say), but if it's gone - it's gone. Nothing else I can rig up ?
That's as I thought, but if no circuit is made to the (presumably) shorted solenoid, the fuse wouldn't blow...?
Which is interesting, because putting the wiring back to standard- the appropriate fuse, or at least, the only one that is labelled for clutch converter lockup in the handbook fuse box diagramme, is NOT blowing.
