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1994 STS IO 34 problem


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Hi,

I am having an IO 34 Problem with my STS, at first I thought it was the PCM, but now I am thinking the IPC is my problem.

Does anyone have any ideas on testing the IPC with out having to replace the unit?

I am thinking I need to check the voltage on the 800 circuit that loops all the computers togeather, as I see it thart should be 3.5 to 5 volts and varing.

Any ideas or thoughts would be great.

John

John

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Besides the code what are your symptoms

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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I am having a traction disabled message in the DIC, high RPM's at idle, just dashes in the avg/instant MPg & range displays. Codes IO34, TO72, I can clear the TO 72 code but the DIC message of traction disabled stays.

Car will crank and run, but boy does it bang going into gear and it is defaulted into 2nd gear only. I thought at first it was the pcu, I switched out with a used unit that I picked up, but it still had the same problems and the addition of no ACP data, I put my orginal PCU back in and went back to just the No PCU data & IO34. When I go into diagnostics it says no PCM data all other units are there, ICP, ACP, TCS, RSS, SIR and I can access them and clear codes.

I have checked the main grounds under the hood, the one by the battery and the one at the alternator..

This is driving me crazy, I really miss my STS.

Any help wpuld be great.

John

John

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  • 3 weeks later...

I am having a traction disabled message in the DIC, high RPM's at idle, just dashes in the avg/instant MPg & range displays. Codes IO34, TO72, I can clear the TO 72 code but the DIC message of traction disabled stays.

Car will crank and run, but boy does it bang going into gear and it is defaulted into 2nd gear only. I thought at first it was the pcu, I switched out with a used unit that I picked up, but it still had the same problems and the addition of no ACP data, I put my orginal PCU back in and went back to just the No PCU data & IO34. When I go into diagnostics it says no PCM data all other units are there, ICP, ACP, TCS, RSS, SIR and I can access them and clear codes.

I have checked the main grounds under the hood, the one by the battery and the one at the alternator..

This is driving me crazy, I really miss my STS.

Any help wpuld be great.

John

John

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Hmm, the how-to section shows IO34 Loss of PCM Data Communication

Traction disabled suggests one type of problem.

Car banging in to gear seem consistent with a traction disabled problem.

Have you changed the brake pads recently? Traction disabled can happen with some models when the brake sensor gets disconnected on the rear brake disks, but I don't recall if that is a 1994 issue.

High RPM at idle would seem a different problem, possibly related to the throttle body needing cleaning.

Bruce

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Hmm, the how-to section shows IO34 Loss of PCM Data Communication

Traction disabled suggests one type of problem.

Car banging in to gear seem consistent with a traction disabled problem.

Have you changed the brake pads recently? Traction disabled can happen with some models when the brake sensor gets disconnected on the rear brake disks, but I don't recall if that is a 1994 issue.

High RPM at idle would seem a different problem, possibly related to the throttle body needing cleaning.

Mine's a 1994 Edorado, and I have the same "traction disabled" message. In my case, it's due to a bad connector at the front left wheel hub. I also have the ABS light on my dash all the time. That could be your issue there. Mine however has never caused any shifting or gear changing issues, at least none that I have noticed.

High RPM could also be the Idle Speed Control motor. That was the case when I had that problem not very long ago.

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See this thread, you should check your grounds per Logan, with the I034, Mike

http://caddyinfo.ipbhost.com/index.php?showtopic=26814

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Thanks guys, This is driving me crazy.

I have checked grounds 100,101,103,105,106,301,302,303,304,305,

Still need to check crawl under the car to check 102,104, and contour myself into the trunk for 400.401,402,403.

I am getting ready to do those and check the voltage at pin M on the alda connecter like Logan reccommended.

I am leaning toward the IPC as my problem, since I did try anotherr PCU and had the same problem.

The only thing that bugs me about my IPC the climate display still shows numbers, I can not tell if the fan kicks into high deforst mode since my blower motor gave up the ghost and was suppose to be my next repair till this occured.

I have the blower motor I guess I should go ahead and put it in to double check, so many things to check so little time.

John

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Thanks guys, This is driving me crazy.

I have checked grounds 100,101,103,105,106,301,302,303,304,305,

Still need to check crawl under the car to check 102,104, and contour myself into the trunk for 400.401,402,403.

I am getting ready to do those and check the voltage at pin M on the alda connecter like Logan reccommended.

I am leaning toward the IPC as my problem, since I did try anotherr PCU and had the same problem.

The only thing that bugs me about my IPC the climate display still shows numbers, I can not tell if the fan kicks into high deforst mode since my blower motor gave up the ghost and was suppose to be my next repair till this occured.

I have the blower motor I guess I should go ahead and put it in to double check, so many things to check so little time.

Just came back in to post a little more, I cranked car today first time since first of week to double check codes.

Now instead of a high idle I have a no idle I have to pummp the gas and feather the gas pedal to get it started and keep it running.

Codes are still the same

IO 34c, IO 52h, To72c.

Still show no PCM data when in diagnostics mode all other systems ok.

When I have the car running the DIC shows "Traction Disabled" only, no other messages if I cycle through the info anything that requires PCM data is out ie: Temp, mpg and the others.

With just the key on engine not running the DIC switches between "Traction Disabled" and "Stop Engine Low Oil Pressure"

Also no brake work done on car.

John

John

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Thanks guys, This is driving me crazy.

I have checked grounds 100,101,103,105,106,301,302,303,304,305,

Still need to check crawl under the car to check 102,104, and contour myself into the trunk for 400.401,402,403.

I am getting ready to do those and check the voltage at pin M on the alda connecter like Logan reccommended.

I am leaning toward the IPC as my problem, since I did try anotherr PCU and had the same problem.

The only thing that bugs me about my IPC the climate display still shows numbers, I can not tell if the fan kicks into high deforst mode since my blower motor gave up the ghost and was suppose to be my next repair till this occured.

I have the blower motor I guess I should go ahead and put it in to double check, so many things to check so little time.

I am impressed, keep up the good work and thanks for posting your progress.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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I dont know if this will help but I found reference to I034 in this document, you should save this location to your favorites, Ill see what I can dig up. Hopefullly someone with a 92 FSM will help out

http://www.scribd.com/doc/11904782/Tests-With-Codes

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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  • 7 years later...
21 hours ago, Jeffery said:

Was this ever fixed mine is doing the same thing 

See this thread also, what symptoms are you.having?

 

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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I am getting i034 and stop engine low oil wait message and traction disabled without it running when switch is 1st turned on everything works then 5 secs later fuel range goes out you can also go into the information button and it will not show engine temp I had a thread were I was getting a p073 engine over heat problem but engine would not be hot I believe you helped me with that also any help will be greatly appreciated

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