Hi guys, my car keeps pulling code p1571. I know that its ASR Desired Torque Circuit but what I dont know is what it does to the car? Does it make it drive differently or make it shift differently? Im just wondering if this is were my no kick down problem is coming from. Thanks for any and all help.

 

Your kickdown problem is the P0748 that you are getting ....

The P1571 should have a matching C1277 in the EBCM (TCS).

Those codes will cause your Traction Control to turn OFF. I'll bet you're getting SERVICE TRACTION CONTROL messages on the DIC. These codes have NOTHING to do with your transmission, the P1571 says that the PCM is receiving a REQUESTED TORQUE signal that is out of the valid range, or is not getting a signal at all.

 

Thanks Steve. Im not getting no other codes that your talking about and Im not getting no service traction control on my dic. The 1571 pulls up weather Im getting on it or not. I was talking to a transmission guy and he thought that my sometime and sometime not down shifting problem was from a dirty mass air meter or even a bad tps but I dont have any tps or maf codes pulling up. He told me that the only thing that the valve in the transmission(p0748) does is cause the tranny to be firm or soft but has nothing to do with it down shifting. Please Pm me your phone # I must of lost it. I would like to talk to you over the phone if you dont mind. Thanks.

 

PM sent .... give me a call at your convenience.

Also, is yours a 1997 ?????

I should have thought of this before .... there is a TSB out for a P1571 that can't be deleted in the 1997 models. It sounds like that is what you have if you don't have the "matching" C1277.

http://forums.corvetteforum.com/show...ighlight=p1571

Scroll down and read the post from Bill Dearborn .... I'll keep looking to see if I can find a copy of the TSB to see if there are more details.

 

Thanks Steve, I read the link and it looks like the 1571 is nothing to worry about but my car decided to downshift once today and take off. Im going crazy trying to figure it out. My car also pulled a "radio u1016" which is lost off communication with pcm. The drivers seat also decided to move into position 1 instead of staying in position 2 when I put the key in the ignition. The car did not pull the P0748 code today after I cleared everything out but Im sure that it will reappear. Im starting to wonder if my battery is causing all my problems. This car has a mind of its own. Thanks for all your help & Ill try giving you a call.

 

The Service Manual has a section in the 4L60-E Chapter that has symptoms.

There is a sympton called "No part throttle or delayed downshifts"

Under this are two columns ....

One column is the component (such as the "Input Housing Assembly") and then follows a list of "causes" that could make that component be the problem.

I'll list the components in bold and then the causes as bullet items ....

Input Housing Assembly

* 3-4 Apply ring stuck in applied position
* Forward clutch not releasing
* Turbine shaft seals missing, cut or damaged

Manual Valve Link

* Disconnected

Valve Body Assembly

* 2-3 Shift valve stuck
* Manual linkage not adjusted
* Spacer plate and gaskets incorrect, mispositioned or damaged
* Looverrune valve stuck
* Orificed cup plug restricted, missing or damaged

Reverse Input Clutch Assembly

* Clutch plate worn
* Reverse input housing and drum assembly cracked at weld
* Clutch plate retaining ring out of groove
* Return spring assembly retaining ring out of groove
* Seals cut or damaged
* Restricted apply passage
* Porosity in piston
* Belleville plate installed incorrectly
* Excessive clutch plate travel
* Oversized housing

Lo and Reverse Clutch

* Clutch plates worn
* Porosity in piston
* Seals damaged
* Return spring assembly retaining ring mispositioned
* Restricted apply passage

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

Let me keep looking at some more possibilities, and maybe someone else can chime in with an idea.

 

Thanks a ton Steve. Im still confused because it works sometimes and sometimes, or I should say most of the time, its not working. You would think that there would be more people having the same problem with there A4's but so far it seems that Im the lucky one, LOL. Im going to play around with the wiring a little more. Thanks again for all your help and I will keep in touch.

 

I've thought about it some more (a VERY dangerous thing for me to do .... ) and here's what I'd consider doing.

While I think it is more likely a hydraulic/mechanical issue I'd first check the wiring at the connector (it is a round 20 wire connector) where it attaches to the transmission (passenger side). It doesn't cost anything to check it, and other than jacking and supporting the rear of the car it is relatively easy to do.

If that doesn't clear the problem, the next step I'd consider is changing the ATF and filter. This requires dropping the pan off the bottom of the tranny. It'll give you the chance to see/smell the ATF. You're checking for a "burned" smell which can indicate problems with the Torque Converter Clutch. Also inspect the bottom of the pan and the filter for signs of metal particles.

I'd recommend that you save small samples of the fluid and any debris you find so that if later a mechanic needs to do further diagnosis they will have something to work with.

Looking at the list of items I posted above, it is probably something like a "stuck 3-4 apply ring" that frees up and then sticks again causing the intermittent problem. With cleaner ATF maybe the problem will clear itself. Issues listed above such as "Belleville plate installed incorrectly" can be crossed off the list as that is not gonna creat an intermittent condition.

Keep us posted.

Steve

 

Steve thank you for all the help. I ended up putting in a new battery and It seems to have solved the problem. I have only driven it for a few miles but Ill keep everyone posted over the next few days. I bought the new battery and installed it thinking it was fully charged since the place that I bought it from told me that it was already charged. Well, I still asked them to put it on a charger and they said it was ready go. I installed it and drove the car and it wouldn't down shift nor did it sound like it was running very well so I put my battery charger on it and it showed that it was only half charged so I let it charge for a few hours and then took it for a drive and I had no problems what so ever. Like I said I will keep you posted as I put a few more miles on it over the weekend to see if the battery was causing all my problems. By the way they did a test on my old battery and it showed that it was bad. It also had a small leak in it. Thanks.

 

If a new battery is the fix for the problem .....



That would be AWESOME ......

I will cross my fingers, my toes, and my last few hairs (I'm REALLY bald) that the new battery fixes the problem.

Please keep us posted .....