: 96 Deville codes pco603 and pco717

02-02-05, 09:37 PM
Caddy runs fine, but Service Transmission message appears after approx 15 minutes of driving in traffic. Never get the message on highway.

Codes show:
pco6o3 - Control Module Long Term Memory Reset

pco717 - Input Speed Sensor Low Input

The car runs great and shifts smoothly. Here's the question: can I live with this or does this critically need to be fixed? If the answer is fix it, is it an expensive repair?

Any help on this would be really appreciated, and thanks in advance.

02-03-05, 11:18 AM
Memory error.... check for clean battery cables.

Input speed sensor....'$20 part $2000 deep' inside the trans is the running joke. Rare...but spark plug wires resting on the engine harness CAN induce a false code. Something to check....

Logan Diagnostic

02-03-05, 11:54 AM
Good information there from Logan Diagnostic... You may also want to search the forums for input speed sensor, as I'm sure there are other posts out there about it that could yield hints and tips for finding and fixing this problem for you. In the blue horizontal bar above, second from the right, click Search and put "input speed sensor" in the box. Read through some of those and you should find what you need to solve the problem.

Good luck... Let us know how it goes with this.

02-03-05, 05:26 PM
I'll check the cable, wiring and harness items this evening, and will search the Input Speed Sensor threads as well.

I really appreciate the help both posts provided.

Mucho Thanks!

02-05-05, 01:28 PM
ok, I checked the battery cable and it's clean and fine. For the wiring and harness - no chance of me diagnosing this.

The car shifts smooth as silk even when the message appears. I see another poster this week with identical codes, so I guess I just volunteered to be the experiment. I'll post an update when things head south.

FWIW, the wife said why don't I look at something new like a Japanese Honda. I showed her the first year depreciation >$3,700. BTW, my research indicated head gaskets are another looming issue. Even if I have to put $3k in the Caddy, this gets me by for a year. I might add: a year driving a luxury sedan who's ride is unmatched, versus an econobox.

I hope my next tranny post is no time soon. Thanks again for the helpful replies.

02-05-05, 05:47 PM
FWIW, the wife said why don't I look at something new like a Japanese Honda. :tisk: Does she not realize, that is grounds for a divorce.

02-05-05, 07:12 PM
"Does she not realize, that is grounds for a divorce."

LOL. I'm a numbers guy, I don't want to go there.:helpless:

02-10-05, 10:01 AM
We have a lot of customers with this same problem , once in awhile they will experience a hard downshift or upshift , most have run the car for over 2 years and a lot of highway driving without any problem except having the light come on. We have not yet found an easy way to repair this problem.

02-10-05, 10:07 PM
Thanks for posting this input. This is good information to know.

12-24-05, 10:22 AM
just checking back in after trading the caddy. i had the input speed sensor code pco717 showing.

someone had suggested it was a tough problem to fix and the caddies ran ok with the code showing, even for a couple years.

on my caddy, despite the code, the car ran fine. almost 2 years. hope this helps.