Tc Not Locking

[notacarlo]

First of all: A couple of months ago I was drining the car and the converter started locking and unlocking in no particular pattern.

Secondly: I got a new tranny from Brian Hofer, and this thing is the ****....period.

So now I am left to diagnose an apparent wiring issue with the TCC.
Today I replaced the tan/black ECM wire completely - still no lockup.

Where else do I need to be looking? What wire supplies 12v to the solenoid? (and don't say the one that goes to the battery )

SO while I wait for replies to my query, I am going to break out a beer and the multimeter - start hunti'n through stuff.

Thanks in advance.

Dan

 

[mikestertwo]

It gets it's power through the brake switch. Check the adjustment on the brake switch.

 

[blackplague]

Hey dan!

Power for the solenoid comes from the IGN switch,to a 10a fuse in the fuse panel, to the brake switch, then down to the 4 pin connector on the trans at pin A. Pin A should be right on top of pin D {tan/black}. The other pins are: 3rd gear switch Pin C {dk green/white} and 4th gear switch Pin B { Lt blue}.
:biggrin:

 

[notacarlo]

thnak you both, let the troubleshoting begin!

 

[notacarlo]

Can I rule out the brake switch if the brake lights still work?

Is there an exact way to set the switch @ the pedal?

Can I run a direct 12v source to the socket on the transmission?

 

[mikestertwo]

It is possible to have the brake lights work and still have the switch misadjusted. With the brake pedal in it's full up position, push the switch up against the brake pedal arm.

 

[PaCemkr86]

any updates on this?

 

[notacarlo]

Yeah Phil, it was a fuse.

I am currently poking red hot metal into my toenails.

It was the ECM/Solenoid 10 amp on the top right corner. Well, at least the TCC is re-wired.

 

[PaCemkr86]

well thats good news.. hows the trans ???

 

[notacarlo]

This transmission isincredible. I forgot what this thing was supposed to feel like. I went to Grainger and go their "new" leak valve and it works like a charm as boost control ($21).

Now it's time to tune, then get it to the Motorplex for some T&T.

Phil, thanks for introducing me to Brian. Networking at it's best.

 

[PaCemkr86]

no problem, good to see ya back in the game..

 

[doberman]

I am having the same problem, ( converter not locking up). I have done voltage tests with the car on stands and everything checks out right. Even put a new TCC switch in the transmission. Is it possible the converter is bad? Any help will be appreciated.

 

[copo]

I am having the same problem, ( converter not locking up). I have done voltage tests with the car on stands and everything checks out right. Even put a new TCC switch in the transmission. Is it possible the converter is bad? Any help will be appreciated.

Did you change the 2 pressure switches? Part # 8683502

 

[doberman]

No, I didnt change the 2 pressure switches. Is that a possible cause for the TCC not locking up? Should I have changed those switches as a maintenance, when I changed the TCC switch, tranny fluid, and filter?

 

[copo]

Yes. I did mine last summer and changed them both since I was already there in case I had a bad one with my locking and unlocking condition.

 

[doberman]

--------------------------------------------------------------------------------

Yes, The fuse is ok. When you say hook a jumper wire from term F of ALDL to term A, do you mean term A of connector on tranny? I hooked a test light from ALDL terminal to ground and drove car up to 65mph. Light on with key on and up to 50mph, then light off. Light off with touch of brake. I also back probed ECM, C7 and C8 terminal according to buick manual with car on blocks and checks out, 12v when car shifts into 3rd and 4th. I have replaced the TC solenoid with a new GM part. Should I think the 2 pressure switches are ok by checking C7 and C8 terminals at ECM?

 

[mikestertwo]

It's "A" to "F" on the ALDL connector. Does it lock when you connect the two. It looks like from all the tests you ran, the converter should lock. You confirmed the trans switches are working by checking "C7" and "C8" on the computer. You confirmed that the computer is commanding the converter to lock when your test light went out when connected to pin "F" on the ALDL connector and you reached 50mph. Now I have to ask the silly questions. Did the converter ever lock since you have had the car? Does the car have a lockup converter in it?

 

[doberman]

TCC tests

Thanks for the quick reply. I have had the car for 3 yrs and it did lock up when I first got it. Gas mileage is alot worse now with it not locking up. Pretty sure it is the original converter. I will try the A to F on the ALDL. Should I try a test light at the connector on the side of the tranny to make sure power is getting there? If so which terminals? Also, can you tell me where to find the VSS box.

 

[mikestertwo]

You should have 12v on pin "A" on the transmission connector. It's a purple wire. Also, make sure the return line is connected. Pin "D" (tan/blk wire) on the trans connector should be connected to pin "F" on your ALDL connector. I think your VSS box is located just above and to the right of your steering column.