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Old 04-27-2010, 09:29 PM   #1
qu1cks1lver56
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Converter Lock Up Harness

So after seeing a couple posts about lockups, I got to thinking I don't really notice mine working, so I did the push the breaks @ highway speeds test and it didn't unlock and lock again. So I looked under the hood, and there's a wire coming off the harness on the vacuum switch that has a plug on it, and nothing's plugged into it. I'm not sure where it's supposed to go but I thought maybe this might have something to do with it. Is this extra wire supposed to have constant/switched power? It has a red/orange colored plug.
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Old 04-28-2010, 05:39 PM   #2
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Re: Converter Lock Up Harness

Anybody?
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Old 04-29-2010, 09:28 AM   #3
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Re: Converter Lock Up Harness

These posts lately got me wondering if mine is working, I really can't tell. But I thought I read some where that if it didn't work it would overheat the tranny. Any ideas?

I just found this info on another site:


Quote:
Although the torque converter clutch is not part of the engine, it can make the car feel like the engine has a problem. The torque converter clutch is also known as a lock up converter. The lockup clutch has many purposes and is part of the transmission. A regular converter in an automatic transmission is made to slip at idle so that the car doesn't move. As the accelerator is pressed the RPM's raise and the torque converter will start to lockup or engage. When the converter engages the car will move.

Even though the torque converter is engaged it never completely engages the way a manual transmission car clutch will. It will always slip a little, which is not very efficient. This is why a manual transmission car gets better gas mileage and has more power than an automatic transmission car. To increase power and mainly fuel mileage, a TCC is added to an automatic transmission.

The torque converter clutch is an electronic clutch that will engage the engine and drivetrain 100 percent. The TCC is made to engage usually only in the top gear when the car is cruising, not accelerating. The lock up converter will disengage when the accelerator is pressed hard enough. Over time the clutch will wear out especially if the vehicle ever towed anything and was operated in overdrive (top gear). This will wear the clutch out prematurely. If you have a tachometer you will see the RPM's drop a few hundred when it engages.

If the TCC is bad one of three things will usually happen. First, the vehicle will tend to rev up and down as it engages and disengages, not being able to keep the converter clutch locked up. Second, the converter clutch will engage randomly in gears that it shouldn't even engage in usually. Third the clutch doesn't want to disengage. As you slow down the vehicle won't downshift and if you try to accelerate the RPM's will be so low that the vehicle will have difficulty moving quickly. In extreme cases the lockup converter will try to keep the vehicle moving as you try to stop at a stop light, or will stall out and die.

Many people think that this problem is coming from their engine because it causes the car to stall. The check engine light will not always show an error for the TCC. Most lockup converters are controlled by a wire or wires that plug into the transmission. It is possible on some models to simply disconnect this plug. This is not a problem and will only cause you to lose a little gas mileage. The RPM's will run slightly higher than before but will not harm anything or be an issue.
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Last edited by Roadrage; 04-29-2010 at 09:29 AM.
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Old 04-29-2010, 11:52 AM   #4
qu1cks1lver56
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Re: Converter Lock Up Harness

Yeah I knew somewhat how they work, I'm just wondering how to properly hook it up. I don't know where that plug on my harness is from or what it's supposed to go to, but I'm thinking it might have something to do with why mines not properly working. It's a reddish/orangish colored plug with 1 wire in it. I'm trying to figure out if it needs power or what, I guess I should hook a meter up to it and see if it has power or anything now. Might do that later today.
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Old 04-29-2010, 02:38 PM   #5
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Re: Converter Lock Up Harness

Here, number 4 is what I think you are looking for.
Attached Images
File Type: pdf TCC wiring and part numbers1.pdf (33.6 KB, 117 views)
File Type: pdf TCC wiring and part numbers3.pdf (117.2 KB, 137 views)
File Type: pdf TCC wiring and part numbers4.pdf (80.6 KB, 91 views)
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Old 04-29-2010, 04:40 PM   #6
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Re: Converter Lock Up Harness

Thanks Bob.
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Old 04-29-2010, 07:36 PM   #7
3r!c84
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Re: Converter Lock Up Harness

i dont think mines working eather
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Old 04-29-2010, 11:01 PM   #8
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Re: Converter Lock Up Harness

how would the routing go on a 6.2 diesel? I don't think the engine makes enough vacuum to have a vacuum switch...I think maybe the signal goes through the TPS, but I'm not sure...my lockup stopped working, so I just went ahead and through power to it constantly...it works, but I want it to work correctly like it should have from the factory...
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Old 04-30-2010, 12:15 AM   #9
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Re: Converter Lock Up Harness

I'm going to try and chase down the wires tomorrow. As far as I know the stock lockup wiring is still there.
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Old 04-30-2010, 06:35 AM   #10
3r!c84
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Re: Converter Lock Up Harness

Quote:
Originally Posted by qu1cks1lver56 View Post
So after seeing a couple posts about lockups, I got to thinking I don't really notice mine working, so I did the push the breaks @ highway speeds test and it didn't unlock and lock again. So I looked under the hood, and there's a wire coming off the harness on the vacuum switch that has a plug on it, and nothing's plugged into it. I'm not sure where it's supposed to go but I thought maybe this might have something to do with it. Is this extra wire supposed to have constant/switched power? It has a red/orange colored plug.
what tranny do you have? th350?
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Old 04-30-2010, 11:09 AM   #11
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Re: Converter Lock Up Harness

th350c
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Old 04-30-2010, 06:43 PM   #12
3r!c84
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Re: Converter Lock Up Harness

mine too.have u found anything yet?
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Old 05-01-2010, 02:36 AM   #13
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Re: Converter Lock Up Harness

No didn't have time to screw with it today.
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