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Code P029 and I027 ?


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the display at my ´95 eldorado say code I027 (PRND321 switsch failure) and the

code P029 (transaxle shift "b" solenoid problem).

Now, I think the car drives exelent without any problems...

The code I027 is not the problem, my problem is the code P029...

Is the transaxle damaged ? Or what is the problem with it ?

What can I do ?

With best wishes from germany...


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The shift solenoids are switches inside the transmission which do need replacement periodically.

See http://caddyinfo.ipbhost.com/index.php?sho...=shift+solenoid which also covered a recall which replaced the ones from 95/96. Since your car is out of warranty it is not eligible for free updates. Not an expensive problem really, if you have a good transmission shop.


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If these are history codes, I would clear them and see if they come back. The PRNDL switch failure may come from driving the car while the shifter isn't in a detent (i.e. between gear selections), a mis-adjusted PRNDL switch, or a loose connector. The solenoid is possibly a connector or wiring issue. If the code doesn't come back, you are done. If it comes back once a week, you should look at the wiring. Failing that, you can get some new solenoids from Rock Auto or DeSimone Cadillac; I know for a fact that DeSimone ships internationally. I've dealt with them and they are the best.


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Hello an thank you "Caddyinfo.com" and "Jims_97_ETC",

these codes are history codes.

If I often shift from "D" to "1", "2" or "3" the code I027 is coming.

If I drive with "D" it´s all correkt.

Now, today I´ve seen the P029 code at first. I hope it´s a wiring problem.

Can an I027 code with wiring problem an P029 code as consequent effect ?

If I think...

I shift from "D" to "P" and the "service engine soon" with P029 code comes...


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Is your car shifting fine up to a certain gear, say 3rd or 4th, then dropping down to 2nd and tripping the P029 code? It will not hurt the car to drive it in second as long as you do not drive cross country or at excessive speeds. I found a reputable transmission shop that is knowledgable of Cadillacs to change my solenoids for $80.00. The solenoids are a common problem, there is an updated shift solenoid set that costs about $50-$60. It is not that hard to change but it is messy. My shop changed mine in about an hour. The solenoids are under the bottom pan. The biggest problem you will have is that the tranny shop might try to convince you that the whole transmission need overhauled rather than just the shift solenoids. Stick to your guns and insist on just changing the solenoids. I think the I027 is set if you shift into park while the car is still moving. There is alot of info on the P029 in the archives.

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