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No lock up, brake light switch?

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Old Jan 14, 2008 | 07:53 AM
  #1  
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Default No lock up, brake light switch?

I lost lock up the other day, and I was pretty pissed to say the least. I pulled the e-brake up and the dash light didnt come on, could that be the problem? It comes on when you start the car along with all the other lights in the dash and the brake lights work too when I hit the pedal. Sorry for asking a dumb question but the search wasnt workin for me.
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Old Jan 14, 2008 | 08:52 AM
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That's not a dumb question dude! I'm fairly certain the e-brake does not have the authority to disable Lock Up.

Is your sevice brake electrical circuit operating properly?

What is the fluid condition?

Have you made any other shnages to the car recently?

There are a multitued of reasons for this to happen, is your SES lamp on?

DO you have a way of getting a scanner on the car and driving it in order to determine if lock up is actually being commanded?

g
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Old Jan 14, 2008 | 09:09 AM
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Fluid is good, no new changes to the car, and as far as the brake circuit goes I dont know, its not throwing any codes and I do not have a scanner to see if lock up isbeing commanded.
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Old Jan 14, 2008 | 09:13 AM
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Unfortunately, we need to know if it is an electircal, software or mechanical issue.

The only way to know that is to communicate with the PCM and determine if the command is being given forLock Up.

g
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Old Jan 14, 2008 | 10:10 AM
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I'm hoping its that switch cause its a little hard for me to believe that the e-brake would lose its signal same time I lose lock up. Stranger things have happened though.
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Old Jan 14, 2008 | 02:04 PM
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Ok well I took it to a friends shop and we hooked his scanner up to it and took it for a ride. The brake circuit opens and closes on the scanner when I hit the brakes so thats workin good. It is sending the lock up command. So I'm guessing my second yank converter took a crap on me?
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Old Jan 14, 2008 | 02:10 PM
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Unfortunately if the PCM is indeed providing the command then yes, the converter clutch has failed.

Have you made any dyno pulls with it locked up?

Is the PCM programmed to Lock Up at WOT?

g
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Old Jan 14, 2008 | 02:38 PM
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no, its programmed to operate normally, I guess I'm gonna have some work ahead of me.
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Old Jan 14, 2008 | 03:05 PM
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I hear ya. When you get it out... take a look at the front cover of the unit (engine side) there is a flat surface that runs the circumference of the unit. That is where the Clutch itself bites in order to provide Lock Up. Look and see if that surface area is discolored, like it's been hot. If it is, then you will know for sure the clutch has failed.

Also, be sure to flush the cooler and replace the filter inside the tranny!

Let me know I can can help in any way. Don't hesitate to call.

Good Luck.

g
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Old Jan 14, 2008 | 08:07 PM
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You can jack it up and peek in there with a flash light to see if its burnt up.
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Old Jan 14, 2008 | 09:13 PM
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I am hesitant to say pull the trans at this point there are several things here that bother me.
1-did the converter suddenly stop locking up or has it been shuddering ?
2-are you getting any check engine lights or codes, Generally unless of course the code has been deleted which I have learned some tuners do this but normally if the PCM comands lockup and it does not ocur you will get a code for component slipping PO1870.
3-Has PWM been deleted either mechanically or in the tune?
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Old Jan 15, 2008 | 12:36 PM
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it did suddenly stop locking but there was like three occurances where it didnt lock up when it was suppose to but it was maybe like a ten second delay but that was a long time ago. No code what so ever and the pwm is still in there and workin as far as I know.
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Old Jan 15, 2008 | 06:11 PM
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The pwm is most likely your problem then. It killed my other converter. Have you jacked the car up and peeked through the hole?
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Old Jan 15, 2008 | 07:24 PM
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I would look through the hole as mentioned to see if the clutch has been slipping but if it was locking normally and suddenly stopped thats odd. When you are looking at the scanner to see if its locking what are you looking at , There are two diffeent areas for lockup , One shows the percentage of lockup allowed , The other is lockup enable/disable This is the most important one.
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Old Jan 15, 2008 | 08:14 PM
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i was looking at the lock up enabled part and the pressure. it was applying full pressure i think. i guess i'll look at it through the hole and see if its burnt up, but let me tell you exactly what it did first. i drove a long distance and got off the interstate and was parked for a little while, than i started it up and it didnt lock up on the streets. i got on the interstate and still no lock up. so i pulled over and checked for codes and didnt see any so i shut it off. i fired it back up and it was locking up and it held it when cruising. but when i gave it some gas, just a little, it slipped and then fully locked and accelerated slightly in lock up. i did it a few times to see if it was gonna keep doing it and after the third time it didnt slip at all just accelereated like normal. got home parked it, next day i start it up to go somewhere, let it warm up fully since its tempremental cause of the cam and no lock up at all. tried shutting it off again and nothing still. does that narrow down what the problem might be any?
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Old Jan 15, 2008 | 08:30 PM
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Well I have to say that if it was enabled and it was clearly not locking up then it is certainly a mechanical issue... especially if it was working and without any tune mods it began this set of symptoms.

Now, that being said... it could be that the hydraulic circuits are fouled, but that is not likely as you mentioned that the fluid was not discolored or burnt smelling. I have seen countless converter clutches fail and not leave the fluid discolored. But, usually it does.

Can you determine if the 1870 DTC reporting has been turned off for some reason? If it is then that would explain the lack of a MIL lamp.

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Old Jan 15, 2008 | 08:39 PM
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i dont know if if it was turned off or not. is there a way to test the pwm solenoid if i take it out? i know the last yank i had it just failed like that and i knew cause i put my old tci back in it and it worked fine. i dont wanna rip into it really but if i have to just to make sure its the converter i will.
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Old Jan 16, 2008 | 11:48 AM
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Is there any way to test the pwm?
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