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2005 DTS
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17 Posts
Discussion Starter #1
I have an intermittent problem with my transmission. When I put it in drive, it really clunks hard, and then shifts real hard and jerky. When this happens, the cruise control will not engage. Other days, it shifts just fine. Even can change on the same trip. Can anyone help with advice?Thanks!
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
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19,250 Posts
I have an intermittent problem with my transmission. When I put it in drive, it really clunks hard, and then shifts real hard and jerky. When this happens, the cruise control will not engage. Other days, it shifts just fine. Even can change on the same trip. Can anyone help with advice?Thanks!
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the FIRST step - ALWAYS - is to check for codes -
 

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2005 DTS
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17 Posts
Discussion Starter #3
Here are the codes I got:
DTC B0429 Temperature Control #3 Rear Circuit Range/Performance
DTC U1000 Class 2 Communication Malfunction

I don't know if these 2 have anything to do with the transmission. Coming home from work it was real jerky. Stopped at the store, the rest of the way home it was fine...
Thanks in advance for any advice.

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Whoops I forgot to give the full prefix.
IPM B0429
RFA U1000
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
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19,250 Posts
Here are the codes I got:
DTC B0429 Temperature Control #3 Rear Circuit Range/Performance
DTC U1000 Class 2 Communication Malfunction

I don't know if these 2 have anything to do with the transmission. Coming home from work it was real jerky. Stopped at the store, the rest of the way home it was fine...
Thanks in advance for any advice.

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Whoops I forgot to give the full prefix.
IPM B0429
RFA U1000
==========================
I don't know if these 2 have anything to do with the transmission.
no -
next check the motor mount -

the front mount is notorious for failing -
ant that allows the motor to flop around -
 

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2005 DTS
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17 Posts
Discussion Starter #6
Never, but I will if you think it will help. It has 67,000 miles on it, and the display says I have 54% transmission fluid life left.

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Wouldn't that cause it to happen all the time? And the cruise control not working when it is in its jerky mode? Then it will shift smooth again, and the cruise control will work fine.
 

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98 eldo/KD54 w/N37,T96,QA1,D55,DS3,U1Z. U3R next
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2,125 Posts
I personally try to change transmission fluid max 60,000 normally 45,000. Transmission fluid takes a lot of abuse so changing it beats changing transmissions

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You could have a sticking solenoid or valve in the valve body, intermittently acting up
 

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Registered
2005 DTS
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17 Posts
Discussion Starter #8
I personally try to change transmission fluid max 60,000 normally 45,000. Transmission fluid takes a lot of abuse so changing it beats changing transmissions

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You could have a sticking solenoid or valve in the valve body, intermittently acting up
If it is a solenoid or valve, any idea on the cost? I have been recommended to an Aamco shop, or should I stick with the dealership here in town? Thanks.
 

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98 eldo/KD54 w/N37,T96,QA1,D55,DS3,U1Z. U3R next
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2,125 Posts
Usually, if a solenoid or electrical fault takes place, there's going to be a code. Has the car been sitting a long time? Has the battery been recently replaced?
 

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2005 DTS
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Discussion Starter #10
Usually, if a solenoid or electrical fault takes place, there's going to be a code. Has the car been sitting a long time? Has the battery been recently replaced?
It's my daily driver, and I have replaced the battery but that was 8 months ago. I may have had a code, but erased it before I knew what I was doing. It should show up again, right? Thanks!
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
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19,250 Posts
It's my daily driver, and I have replaced the battery but that was 8 months ago. I may have had a code, but erased it before I knew what I was doing. It should show up again, right? Thanks!
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if the fluid is red - like cherry KoolAid -
and doesn't smell "burned" or stink -
changing the trans fluid is a waste of time and money -
and will NOT "fix" anything -

I have been recommended to an Aamco shop
aamco - and other "chain" trans shops -
are the LAST place I would take my car -

find a local - independently-owned shop -

update your profile to include your location -
there might be a member close to you with a recommendation -
 

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2005 DTS
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17 Posts
Discussion Starter #13
After 2 days of driving fine, my problem cropped up today on my way home. And I have a new code.

DTC IRC U1016 Loss of Communications with PCM. This sounds more serious. Anyone have any ideas? I supposed to get my tranny fluid change Friday. Thanks in advance!
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
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19,250 Posts
After 2 days of driving fine, my problem cropped up today on my way home. And I have a new code.

DTC IRC U1016 Loss of Communications with PCM. This sounds more serious. Anyone have any ideas? I supposed to get my tranny fluid change Friday. Thanks in advance!
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"U" codes come and go often -
and are usually a simple - one time computer glitch -

I would simply clear the code - and not worry about -
UNLESS the same "U" code appears regularly -

I supposed to get my tranny fluid change Friday.
waste of money -
 

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2005 DTS
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17 Posts
Discussion Starter #15
I took my DTS into a transmission shop today. He was able to pull a code that did not show up when I pulled codes viathe dash. He used his fancy computer and up came this code: P0502 Vehicle Speed Sensor (VSS) Circuit Low Input. Could this be the source of all my shifting trouble? Along with the U1016 loss of communication with the PCM? I am having this sensor replaced and wiring checked next week. Any advice, I thank you all in advance!!!
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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The VSS has a big effect on transmission operation - it also drives the speedometer readout via the PCM and DIC. Does your speedo work properly ?

The VSS is on top of the right transmission output shaft housing - about a foot in front of a passenger's toes.
 

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2005 DTS
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17 Posts
Discussion Starter #17
The VSS has a big effect on transmission operation - it also drives the speedometer readout via the PCM and DIC. Does your speedo work properly ?

The VSS is on top of the right transmission output shaft housing - about a foot in front of a passenger's toes.
Yes, the speedo has worked just fine. Is the VSS hard to get to? The shop told me if I have to replace any solenoids, I am looking at 2K + because you have to drop the transmission to get to them. True? Thanks for your time!
 

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98 DeVille, 97 DeVille d'Elegance
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7,345 Posts
Since your code point to pcm wiring you may want to start there.. If the VSS was bad it should throw a code and can be changed in the car(not easily as it's tight).
I seem to remember connection issues at pcm solved by cleaning or even jjst disconnecting and reconnecting.
 

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2005 DTS
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Discussion Starter #19
To close out this thread, It seems it was the VSS and the wire connector. I have not had that hard shifting issue for over 3 months now. It did shift a little strange the first month or so, but seems to have cleared up. Someone mentioned the battery being disconnected? And these cars "learn" how you drive, etc?
 
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