'92 4L60... SOLVED!

[Doober]

... in my truck. The converter isn't locking up, I don't think it has since I got it. I noticed it a couple months ago, but haven't had much of a chance to check everything yet. I used the ALDL port to try to force it to engage with no luck. My next step is making sure the wiring down to the plug is ok, but other than that I'm afraid something may actually be wrong.

Any ideas besides the external things (wiring, computer, etc.) I can check myself?

 

[big-angry-hillbilly]

Re: '92 4L60...

Brake switch, high gear switch in the trans, vacuum switch, wiring....

I can get you a simplified way of lockup if you like, one wire.

PM me and I'll draw it up for you with my wicked paint skills.

-B.A.H.

 

[Doober]

Re: '92 4L60...

:lol: I have a Haynes manual and have already been into the wiring of an '88 pickup.

I was just wondering if there were any TSBs or the like on the lockup converter. I think this one's been rebuilt, it sure seems to shift nice & firm for a 214k-mile truck.

 

[Doober]

Re: '92 4L60...

Bugger...

So I finally got around to tracking down my non-lockup issue. I have 12v down to the plug on the harness, but the circuit inside the trans is open ](*,) So it looks like I'll be replacing the solenoid (possibly the harness, or part of it) when I change the fluid/filter. I've been needing to do this since I'm taking the truck on a ~4,200 mile round-trip to AZ to help my aunt move (gotta plumb in the aux. cooler I have layin' around too). Let's hope the 217k-mile truck makes it [-o<

 

[Doober]

Re: '92 4L60...

So everything's apart... I took the solenoid/harness out, and it seems to be working, I just have to tap on it for it to open back up (not sure if that's normal with it outside the trans). On the up side the filter didn't look too bad, there was a very little bit of material, but nothing to be worried about yet... I don't know how long it's been since the oil/filter/magnet's been changed, but the fluid is a bit dark, I'm thinking a trans flush may be in order, but I'm pretty sure they're quite expensive.

Can anyone tell me what temperature the temp. switch needs to force the converter into lockup? I was using a heat gun on it and it had to be pretty hot before it would close the circuit.

 

[Doober]

Re: '92 4L60...

Crapcrapcrapcrapcrap... I hope I don't have to buy a torque converter because of a bad tcc So far I've replaced the socket on the trans itself (tabs on the old one broke while removing it to be cleaned), the solenoid (circuit is good inside the trans, verified @ the socket), and I replaced the pins in the connector because I thought they may not be making contact. The computer seems to be working (voltmeter across the tcc/ground on the ALDL goes to 0 when tcc should lock up), and no codes. I don't THINK the brake switch would be causing it, I guess that would be the next plan of action eh?

 

[Doober]

One last thing I checked (it's always the last place you've checked/looked right? :roll. Wound up being the brake light switch. The $9 part cost me about $90 in parts/fluid (minus $25 or so from the fluid/filter change I was already planning on).

Here's the filter... Truck has 216,000 miles on it.