I wired up a switch to manually lock up the TCC this weekend, cause the lockup never happens on its own. I wired it up to the upper left and right wires going to the ALDL connector. I pulled out my voltmeter and discovered I have no voltage coming from the upper left wire. The fuse for this circuit is fine. Any ideas? The brake switch is adjusted fine and the connector is plugged in. Its also connected at the tranny.
No TCC voltage
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salvageV6
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1. What fuse did you check?
2. Check for power on the pink/blk wire and the purple wire on the brake switch, key on test, foot off the brake.
2. Check for power on the pink/blk wire and the purple wire on the brake switch, key on test, foot off the brake.
I dont know what terminal A is. Its the upper left pin, and then the upper right (ground). I read about the paper clip trick, and decided to set a switch up there instead. In the process I found there was no voltage with the key on. It looks like a brown with a black stripe wire. i cant find where this wire leads.
This is killing me. Im absolutely desparate to fix this problem cause if I dont improve my mileage somehow, Im going to have to sell the car. And I definetely dont want that.
I also just discovered that my fuel pressure drops like 10 psi in 5 minutes after I shut the car off. Is this acceptable? My stock injectors took like 6 hours to completely bleed down pressure.
This is killing me. Im absolutely desparate to fix this problem cause if I dont improve my mileage somehow, Im going to have to sell the car. And I definetely dont want that.
I also just discovered that my fuel pressure drops like 10 psi in 5 minutes after I shut the car off. Is this acceptable? My stock injectors took like 6 hours to completely bleed down pressure.
salvageV6
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It's a relatively simple system.
ECM/SOL fuse provides +12 key on, through the brake switch on the colored wires listed above.
+12 goes out the C100 main harness connector under the wiper motor on the PURPLE wire down to the tranny plug PIN A as noted by Chris.
Check for +12 on the purple wire connector pin A.
TAN/BLK wire will be grounded either from the ECM or ALDL port to ground via your switch.
Ground locks up the converter by the ECM normally this is on PIN D at the tranny connector.
ECM/SOL fuse provides +12 key on, through the brake switch on the colored wires listed above.
+12 goes out the C100 main harness connector under the wiper motor on the PURPLE wire down to the tranny plug PIN A as noted by Chris.
Check for +12 on the purple wire connector pin A.
TAN/BLK wire will be grounded either from the ECM or ALDL port to ground via your switch.
Ground locks up the converter by the ECM normally this is on PIN D at the tranny connector.
Thanks! The owners manual said that the check engine loght, and the other bulbs, as well as the TCC solenoid are all run through the same fuse, which was the bulbs, or lamps or dash lights (cant remember the name) fuse. Its a 25 amp fuse at the bottom. This ECM/SOL fuse wasnt mentioned as part of the circuit. If I pull that fuse, will I lose all my programmed parameters with the extender chip?...since after all, it says ECM. What does SOL stand for? **** out of luck?
salvageV6
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Solenoids.
That's what the ECM is controlling.
Won't kill anything but your A/C, cannister purger solenoid, WASTEGATE solenoid, fan delay relay, and EGR solenoid.
Now get out there and check for power.
If your meter reads ohms, use that scale and check the tan/blk wire connector off the tranny pin D to ground.
It should read low ohms to ground when you throw the switch you installed, key off connector off no power test.
That's what the ECM is controlling.
Won't kill anything but your A/C, cannister purger solenoid, WASTEGATE solenoid, fan delay relay, and EGR solenoid.
Now get out there and check for power.
If your meter reads ohms, use that scale and check the tan/blk wire connector off the tranny pin D to ground.
It should read low ohms to ground when you throw the switch you installed, key off connector off no power test.
I cant check this till I get home. I pray to the almighty allah that its just the damn fuse. My A/C isnt charged so Ive never used it, dont know about the cannister purger, my wastegate solenoid isnt connected, dont know about the fan delay relay...all I know is the fan works, and I dont know if the EGR is working. If i jump the A/C connector with a paper clip, Im able to program with my extender....does this tell you anything?Originally posted by salvageV6
Solenoids.
That's what the ECM is controlling.
Won't kill anything but your A/C, cannister purger solenoid, WASTEGATE solenoid, fan delay relay, and EGR solenoid.
Now get out there and check for power.
If your meter reads ohms, use that scale and check the tan/blk wire connector off the tranny pin D to ground.
It should read low ohms to ground when you throw the switch you installed, key off connector off no power test.
salvageV6
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No. 
Tells me you should leave early and go fix da Buick.
Lots of problems and mysteries to solve.
PS: Usually it's the brake switch, could be the A/C blowing the ECM/SOL if the compressor clutch is shorted out or seized up.
Lots of wiring in the car if shorted or f'd up could take out that fuse.
Shorted TCC solenoid wiring inside the tranny too.
Tells me you should leave early and go fix da Buick.
Lots of problems and mysteries to solve.
PS: Usually it's the brake switch, could be the A/C blowing the ECM/SOL if the compressor clutch is shorted out or seized up.
Lots of wiring in the car if shorted or f'd up could take out that fuse.
Shorted TCC solenoid wiring inside the tranny too.
Well I got busy on the pos last night and found something interesting.
First I cheked the ecm/sol fuse. It was fine.
I checked power coming to the brake switch. I have 12V on the red wires.
I pulled the brake switch out to see if the contacts were good. They were a little dirty so i cleaned them up and reinstalled it.
I dropped under the car to check power and lo and behold- some ass pulled the purple wire out of the connector, and zip tied it up and out of the way. I figured there must be something wrong inside that theyre just trying to protect. i didnt care, so I put the purple wire back in the connector and reinstalled the connector. i took the car for a spin, and there was still no lockup, so I checked for power on the purple wire. I have power.
So WTF is this? I figure this is either from there being a non lockup convertor in it, or the solenoid is bad. Which seems more likely?
First I cheked the ecm/sol fuse. It was fine.
I checked power coming to the brake switch. I have 12V on the red wires.
I pulled the brake switch out to see if the contacts were good. They were a little dirty so i cleaned them up and reinstalled it.
I dropped under the car to check power and lo and behold- some ass pulled the purple wire out of the connector, and zip tied it up and out of the way. I figured there must be something wrong inside that theyre just trying to protect. i didnt care, so I put the purple wire back in the connector and reinstalled the connector. i took the car for a spin, and there was still no lockup, so I checked for power on the purple wire. I have power.
So WTF is this? I figure this is either from there being a non lockup convertor in it, or the solenoid is bad. Which seems more likely?
salvageV6
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I do not play a mind reader on the internet.
Do you have a good ground from your switch or ECM to the tan/blk wire to command the lockup?
Two signals necessary to get lockup to occur.
Other than that perhaps the previous owner can answer your questions.
Or you can try reading accross A + D with an OHMMETER and see if you get 20 ohms or so on it meaning the solenoid is in place and wired up.
This is a connector and key OFF test.
Do you have a good ground from your switch or ECM to the tan/blk wire to command the lockup?
Two signals necessary to get lockup to occur.
Other than that perhaps the previous owner can answer your questions.
Or you can try reading accross A + D with an OHMMETER and see if you get 20 ohms or so on it meaning the solenoid is in place and wired up.
This is a connector and key OFF test.
Sorry if this sounds stupid, but what 2 signals are necessary? At the brake switch, There is a connector with 3 wires. Ther are 2 reddish looking ones on one end, and a purple on the other. I have power at the red ones but not the purple. At the connector by the trans, I do have power at the purple wire. This confuses me a bit. Is this purple wire not the same one as the one at the brake switch?
At my manual switch, I have 1 wire going to the tan/blk wire, and the other on the ground wire, both on the ALDL connector. Crossing these wires simply provides a ground for the solenoid, right?
Ill get to checking the resistance at the solenoid later tonight when I get home.
Thanks for all the help.
At my manual switch, I have 1 wire going to the tan/blk wire, and the other on the ground wire, both on the ALDL connector. Crossing these wires simply provides a ground for the solenoid, right?
Ill get to checking the resistance at the solenoid later tonight when I get home.
Thanks for all the help.
salvageV6
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You are welcome and you are right.
Power must be on the purple tranny connector wire at all times the key is on and your foot is OFF the brake for solenoid to have +12 power.
ECM or your added switch provides the ground signal to cause lockup to occur.
If you have purple power with the key on at the tranny let's assume all is good at the brake switch for now.
Need to verify if the ground signal is getting to the tan wire at the tranny connector from your switch.
And you need to read the two transmission pins A+D to see if it reads about 20 ohms or so.
It's not complicated circuitry but there are switches, connectors, etc. on both the hot and ground wires to the solenoid.
Power must be on the purple tranny connector wire at all times the key is on and your foot is OFF the brake for solenoid to have +12 power.
ECM or your added switch provides the ground signal to cause lockup to occur.
If you have purple power with the key on at the tranny let's assume all is good at the brake switch for now.
Need to verify if the ground signal is getting to the tan wire at the tranny connector from your switch.
And you need to read the two transmission pins A+D to see if it reads about 20 ohms or so.
It's not complicated circuitry but there are switches, connectors, etc. on both the hot and ground wires to the solenoid.
salvageV6
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Purple wire is A, tan/blk stripe wire should be D.
It should be marked on the connector somewhere if you get it clean enough and can see it up close with good light.
It should be marked on the connector somewhere if you get it clean enough and can see it up close with good light.
Thanks! If a tranny gets set up for a non lockup convertor, does the TCC solenoid get eliminated all together, or do they cut the wires? So if I get no continuity between A and D, I assume that means either the solenoid is fried, or its not even there, right?
salvageV6
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An open circuit means the TCC could be melted open, wire cut, or not even in there, but it certainly won't be working.
Connector off test just probe the connector on the transmission those pins.
I don't know about running non-lockups, I drive my car so I need the lockup feature.
Connector off test just probe the connector on the transmission those pins.
I don't know about running non-lockups, I drive my car so I need the lockup feature.
Ok, Ive got some info.
I tested the A and D pins last night and got 30 ohms, so the solenoid is there.
After reinstalling the purple wire in the connector, that the old owner had removed for some reason, I now had voltage to the tan/blk stripe wire on the ALDL connector. My switch was wired up wrong, so I re-wired it, and now my blue LED on the switch lit up when i switched on. I took it for a spin, and when I flip the swiych on, there is absolutely nada. Nothing happens. But when I touch the brakes, the LED turns off which proves my brake switch is working. Another interesting thing happens. When i hit overdrive, the LED shuts off. If I let off the gas and slow down in overdrive (im not in 3rd gear...Im still in OD), but dont touch the brakes, the light comes back on. It seems like the light goes off when the computer commands TCC lockup. But why the light would turn off (voltage being cut to the switch on its own), is beyond me.
Theres yet another interesting thing going on. The extender turns lean cruise on, 10 seconds after the computer commands TCC lockup. My lean cruise does work as shown by my low cruise millivolts on the scanmaster, after Ive been at a steady speed for about 10 seconds. I unplugged my speedo cable as an experiment, and all of the sudden, my lean cruise stopped working. Plug the cable back in, and wala, the lean cruise works again. So its obvious that the computer thinks TCC is locked. But why does my LED turn off when the computer thinks its locked? Im absolutely positive that there is no real locking going on. My rpms dont drop, and the convertor still slips alot. There is a 600-800 rpm spread between going uphill and downhill of the freeway (going through mountains).
I still have yet to pull my converter cover off to check if its a lock or non lock convertor.
This is confusing as all hell!
I tested the A and D pins last night and got 30 ohms, so the solenoid is there.
After reinstalling the purple wire in the connector, that the old owner had removed for some reason, I now had voltage to the tan/blk stripe wire on the ALDL connector. My switch was wired up wrong, so I re-wired it, and now my blue LED on the switch lit up when i switched on. I took it for a spin, and when I flip the swiych on, there is absolutely nada. Nothing happens. But when I touch the brakes, the LED turns off which proves my brake switch is working. Another interesting thing happens. When i hit overdrive, the LED shuts off. If I let off the gas and slow down in overdrive (im not in 3rd gear...Im still in OD), but dont touch the brakes, the light comes back on. It seems like the light goes off when the computer commands TCC lockup. But why the light would turn off (voltage being cut to the switch on its own), is beyond me.
Theres yet another interesting thing going on. The extender turns lean cruise on, 10 seconds after the computer commands TCC lockup. My lean cruise does work as shown by my low cruise millivolts on the scanmaster, after Ive been at a steady speed for about 10 seconds. I unplugged my speedo cable as an experiment, and all of the sudden, my lean cruise stopped working. Plug the cable back in, and wala, the lean cruise works again. So its obvious that the computer thinks TCC is locked. But why does my LED turn off when the computer thinks its locked? Im absolutely positive that there is no real locking going on. My rpms dont drop, and the convertor still slips alot. There is a 600-800 rpm spread between going uphill and downhill of the freeway (going through mountains).
I still have yet to pull my converter cover off to check if its a lock or non lock convertor.
This is confusing as all hell!
salvageV6
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First off you need to know how the light or LED in your switch is wired internally to the switch.
Also we need to know how you wired the switch or re-wired it.
I would use a normal UNlighted switch 2 position ON-OFF.
Tie one side to a good ground on the car, nice chunk of metal under the radio or to the radio case.
Next run the other side of the switch to a meter with the other probe going to ground.
When you throw the switch you should get a nice low ohm reading to ground on the meter.
After that put a wire on the second switch terminal and put it to pin F of the ALDL port should be tan/blk wire I believe.
Then if it don't lock up when you throw the switch you don't got a lockup converter in there or it's dead.
Also we need to know how you wired the switch or re-wired it.
I would use a normal UNlighted switch 2 position ON-OFF.
Tie one side to a good ground on the car, nice chunk of metal under the radio or to the radio case.
Next run the other side of the switch to a meter with the other probe going to ground.
When you throw the switch you should get a nice low ohm reading to ground on the meter.
After that put a wire on the second switch terminal and put it to pin F of the ALDL port should be tan/blk wire I believe.
Then if it don't lock up when you throw the switch you don't got a lockup converter in there or it's dead.
Its an on/off rocker switch, with 3 terminals. Now this is from memory, but I'm 90% sure im right.....One end is ground, the middle is load (the LED is powered between ground and load), and the far end is source. The tan/blk stripe wire (top left)on the ALDL is wired to source on the switch, and the ground wire (top right) on the ALDL goes to ground on the switch. Its a polarized switch, so it cant be wired backward, or the LED wont light and the current wont flow through when switched. I accidentally had wired it backward before. Im not using the middle terminal (load), so I dont know how the LED is working. I DMM'd everything, and I think its wired ok, but Im by no means an electrical expert. No current is flowing through when the switch and LED are off, and it does flow through when on. I know it would be better to ground it to the car, but ultimately, the black ground on the ALDL does run to the car....unless having it go to the ground wire is screwing up other signals going on???? How should a switch with 3 terminals be wired up?
