mreperf Posted September 24, 2011 Report Share Posted September 24, 2011 Just as merged onto the highway tuesday and got up to speed my 97 seville felt like it went into neutral. I gave it some gas and at 3500 rpm's it excelerated and when I let of the gas it again felt like neutral. I crept home at 35mph which was about 3500 rpm's because of only one gear. This same thing ,(only one gear, idled at 2500 and ran like crap) happened last year and ended up being the computer, I had one reflashed and was good till now. So when I checked things out at first I thought the idle control motor went bad because it was idleing high and I never suspected the computer again. After putting it on the scanner I determined it was the computer and ordered another one. Put it the next morning and all was well till about 1 hour ago when it happend again in the same exact spot getting on the highway. Maybe I just need to take the back roads. Obviously something is burning out the computer. Does it sound like a switch in the trans is bad and overheating something in the computer which happens to run on the same power supply that feeds the idle control switch. Just guessing but why has each time been just has it gets ready to shift into high gear. And each time it has affected the idle control. I know it's time for a new car but I need to buy my son his first new truck but this is getting really old. Please don't tell me it's something in the trans and I have to take that thing out. That might be the final straw. Any ideas. Thanks all. Link to comment Share on other sites More sharing options...
Texas Jim Posted September 24, 2011 Report Share Posted September 24, 2011 What codes does it have? Run the codes... write them down and post them here. We need the codes to do proper diagnostics. Link to comment Share on other sites More sharing options...
mreperf Posted September 24, 2011 Author Report Share Posted September 24, 2011 The only codes are P0601 current P0603 history Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 24, 2011 Report Share Posted September 24, 2011 You said you had one REFLASHED...... See This FLASHING IS NOT ALLOWED...... How did you reflash yours? DTC P0601 Control Module Read Only Memory (ROM) Circuit Description The PCM EPROM contains data which isessential in running the engine and transaxle. DTC P0601 checks the integrityof this data. The EPROM data is divided into two halves or sides in the EPROM.The integrity of the data is checked by adding up the data in all locations ofthe EPROM. This is called the checksum. If the checksum does not equal what itshould, then DTC P0601 is set. [/url] Conditions for Setting the DTC Test Condition Test continuously. Failure Condition The checksum indicates a datafailure. Action Taken When the DTC Sets Flashing of the PCM is not allowed. The PCM will illuminate the malfunction indicator lamp (MIL) when the diagnostic runs and fails. The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records. Conditions for Clearing the MIL/DTC The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail. A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail. A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test. Use a scan tool to clear DTCs. Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation. Test Description Number(s) below refer to the stepnumber(s) on the Diagnostic Table. This DTC indicates an internal PCM problem. 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 Link to comment Share on other sites More sharing options...
mreperf Posted September 24, 2011 Author Report Share Posted September 24, 2011 No idea where they come from but my local parts store takes my vin#'s and the next day I go pick up a new one and exchange my old one. Link to comment Share on other sites More sharing options...
Texas Jim Posted September 25, 2011 Report Share Posted September 25, 2011 Mike...it is an EPROM.... Erasable / Programmable Read Only Memory. I know it says not to reflash it...but with the proper equipment, I don't see why it couldn't be reflashed. You and I can't do it, but I would think that a properly equipped shop with correct programs for his VIN could do it. I see big problems arising if the internal integrity of the PCM itself is bad. That may be why none of the replacements are lasting any length of time. They were really no good from the beginning... Just my humble opinion... Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 25, 2011 Report Share Posted September 25, 2011 Jim, I am only repeating what the service manual states I was unaware that he was replacing the the EPROM only and not the entire PCM 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 Link to comment Share on other sites More sharing options...
Texas Jim Posted September 25, 2011 Report Share Posted September 25, 2011 Jim, I am only repeating what the service manual states I was unaware that he was replacing the the EPROM only and not the entire PCM Understand that. That's why I "QUALIFIED" what I was saying... On some of the older ones...(like my 1985 Fleetwood)...when you replaced the PCK, you moved the EPROM over to the new PCM. But I don't think that is the way it is this users case... Just based on what mreperf said.... SOMEONE... SOMEWHERE seems to be reflashing PCM's...or at least trying to.... Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 25, 2011 Report Share Posted September 25, 2011 Yes, I dont think the 97 has a separate EPROM, Actually looking back I read the diagnosis chart wrong, it doesnt state that its not flashable it states its not flashable when the DTC is set.... so my mistake... 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 Link to comment Share on other sites More sharing options...
mreperf Posted September 25, 2011 Author Report Share Posted September 25, 2011 I'm not sure what can or can't be done as far as properly reflashing these things but I do know is all the repair shops around here all go here to get their stuff fixed. It came in a AC-Delco box with lots of papers and instructions and warranty papers. They have a cheaper no-name brand but was told for my own stuff to not use them. That aside any ideas what direction I should start checking or is it time to put this car down. Is the pcm the little board or chip that is located under the two bolt cover? Is that corrupted and what is screwing things up? What do you do if so? And why would it happen in the same exact time getting ready to shift into high gear? Could it be a switch in the trans causing something to draw to much amperage and burn it out? Link to comment Share on other sites More sharing options...
mreperf Posted September 27, 2011 Author Report Share Posted September 27, 2011 Should I take it that there is little chance in finding out if this is repairable or not. I don't mind spending some time in checking things but I have no idea where to start. Something has to be burning these things out. Sure don't want to waste the effort in replacing another one without at least trying something else first. But if it's time to put her down, it's time. Maybe someone can use all the new parts that have been dumped in this car over the last few years. Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 27, 2011 Report Share Posted September 27, 2011 You need to go back to square one You need to extract all codes write then down so we can see what is going on again Explain what is going on with the car, what is wrong Honestly, we have NEVER heard of ANYTHING other than STUPIDITY damaging a PCM/ECM. And that person hooked up the positive and negative cables at the battery and smoked the system. Yes PCM/ECMs have gone bad, but we have NOT seen something outside of the PCM/ECM damage it 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 Link to comment Share on other sites More sharing options...
mreperf Posted September 28, 2011 Author Report Share Posted September 28, 2011 It first happened about one year ago when going down the highway at speed I lost all but one forward gear. The instument cluster lit up like a christmas tree, as I got it slowed down I found it still had low gear and was idleing at 2700. I crept to my shop and put it on the scanner to find a code of P060. A freind told me where to go get a new computer after giving them my vin#s. They put in my unit under the 2 bolt cover and away I went. It started right up and was perfect for year. Then last week while merging onto the highway the same thing happened except not all the lights on the cluster. It was stuck in first gear and wouldn't shift and the idle was at around 2500. I was certain it had to be something else but it was putting out the same P060 code again. Because it was under one year they gave me another one and it again starated right up and was perfect for 2 days till it happened right at the same place getting on the highway just as it shifted into high gear. When it fries what ever it is it's on the same circut as the idle control motor and thats why it idles high. Something is causing them to burn out. Any ideas? Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 29, 2011 Report Share Posted September 29, 2011 Are you still getting a P0603 code in history? Have you been disconnecting the battery at all? 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 Link to comment Share on other sites More sharing options...
mreperf Posted September 29, 2011 Author Report Share Posted September 29, 2011 Yes P0603 history is stillthere and no battery has not been disconnected Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 29, 2011 Report Share Posted September 29, 2011 Yes P0603 history is stillthere and no battery has not been disconnected I think that this P0603 is a hint to your problem. It means that the power to the PCM is being interrupted somehow either by the 12V feeds, grounds, or battery itself 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 Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 29, 2011 Report Share Posted September 29, 2011 See this thread, its your problem, pay attention to Beezlebob, he is known to this board and knowledgable http://www.cadillacforums.com/forums/cadillac-forum/t-19046.html As I said you have something going on indicated by the P0603 code which indicates a power problem 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 Link to comment Share on other sites More sharing options...
the gold2 Posted September 29, 2011 Report Share Posted September 29, 2011 Do you think the fuse to the PCM may be bad or maybe not the correct amp? Check it for good measure. Link to comment Share on other sites More sharing options...
mreperf Posted October 15, 2011 Author Report Share Posted October 15, 2011 Just wanted to inform you all on the results. The parts store exchanged my computer and after installing all is well so far. They got my new one from a different vender that charges a little more but had better results and less returns. The only thing that was different from the first 2 times was this time I had to wait for the security system to reset before it would start. It would turn over but wouldn't fire. But after waiting on that it has been perfect so far. Knock on wood. I still think it's time for something newer though. Thanks everyone for your help and ideas it really helps. Link to comment Share on other sites More sharing options...
BodybyFisher Posted October 15, 2011 Report Share Posted October 15, 2011 Oh good, I am glad you got it straightened out 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 Link to comment Share on other sites More sharing options...
mreperf Posted April 2, 2012 Author Report Share Posted April 2, 2012 Just when you let your gaurd down and everything is running good, it all comes to a crashing halt. I last posted on Oct 15 2011 that all was well with my newly reflashed computer it has done the same thing and thrown a P0601. Still runs, idles high,won't shift. After the last time was fixed I put new negative and positive cables along with a new battery cause the piggy-backed positive cables looked crappy and the negative had some green in it. Thought this was added insurance. Guess not. What the hell could be killing these things. Now the third new on and from different vendors. Is there too much of a draw somewhere? Link to comment Share on other sites More sharing options...
the gold2 Posted April 11, 2012 Report Share Posted April 11, 2012 Man I wonder if you'd have better luck pulling a computer from a pik n' pull yard?? Would a lower amperage fuse for the computer catch a surge before it does damage??? bummer. Link to comment Share on other sites More sharing options...
BodybyFisher Posted April 11, 2012 Report Share Posted April 11, 2012 Any other 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 Link to comment Share on other sites More sharing options...
mreperf Posted April 14, 2012 Author Report Share Posted April 14, 2012 Another new computer installed and no codes at all. Until it kills this new one. New alternator, battery, negative and positive cables. Link to comment Share on other sites More sharing options...
the gold2 Posted April 19, 2012 Report Share Posted April 19, 2012 This is pure speculation but what if it is a scraped or mouse bit wire laid partially bare that hits metal periodically (intermittent) when the chassis twists, turns or hits a bump in the road?? or maybe wire harness is hitting a bare screw tip somewhere? Tough call. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.