mrmossif Posted November 27, 2012 Report Share Posted November 27, 2012 I have a P0231 and a dead car. I was probing around the 20 way transmission harness connector with a test light trying to solve a P0717 input speed sensor problem and after that I had a dead car with a P0231. I did what the flow chart said to try and solve the P0231 and figured I burnt out the pcm by probing around the transmission connector so I bought a pcm and flashed it and same thing. I also get the service fuel system on the cluster. Any feedback would be great. Thanks. Link to comment Share on other sites More sharing options...
rockfangd Posted November 28, 2012 Report Share Posted November 28, 2012 first off Welcome to Caddyinfo forum. first off I would retrace everything you have taken apart and reassembled. check all fuses and relays under the hood in the electrical center and behind the back seat in the trunk left side lower. You may have blown a fuse GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
BodybyFisher Posted November 29, 2012 Report Share Posted November 29, 2012 One thing I was told was NOT to probe the PCM side of that connector ONLY the transmission side, or, you risked damaging the PCM. Explain what you mean by PROBiNG.. 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...
rockfangd Posted November 29, 2012 Report Share Posted November 29, 2012 i also remember that. I only probe the trans side carefully. GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
BodybyFisher Posted November 29, 2012 Report Share Posted November 29, 2012 Please explain this statement also I have a P0231 and a dead car What do you mean by DEAD CAR? Have you tested the battery? 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...
mrmossif Posted November 30, 2012 Author Report Share Posted November 30, 2012 Thanks for welcoming me. By a dead car I meant it won't run it does crank. I did probe the engine harness side with a test light and it was not a low impedance light. This is what it says to do in the service manual for a P0717 code. I did probe other contacts that I was not directed to do. So I figured I burnt the computer, I got a new pcm and flashed it to the car. Same thing car cranks and will not start and also displays service fuel system with a P0231 code. I retraced everything I did and checked all fuses and relays. I have got the car running by jumping the ignition relay 1 on the driver side strut tower. But that throws a bunch of codes mass air, evap, some tranny codes, etc.... I did take the engine side 20 way transmission plug gray connector off in order to take the wire loom off in order to clean all the tranny fluid off of the harness. I did not take any pins out of the connector but they did look like they shifted very very slightly in the connector. I will take another look and make sure that the connector is connected properly. I'm lost to why I'm getting the P0231 code when the wires I tested were all transmission wires. I realize I could have shorted the pcm and that would explain the code but I replaced the pcm. Any feedback would be great thanks. Link to comment Share on other sites More sharing options...
BodybyFisher Posted November 30, 2012 Report Share Posted November 30, 2012 You are getting a code that the fuel pump does not have power P0231 - Fuel Pump Feedback Circuit Low Voltage. Listen at the fuel filler its not likely that you hear the fuel pump run when you turn the key to ON. I have had that relay center apart by the strut tower, but it seems that you have checked everything so this is an odd problem, I dont think this has anything to do with the tranny connector but that is a guess. Try a known good relay in the fuel pump relay location. I trust you looked at each relay for green/white corrosion? Try resetting the connection at the PCM, but in a way you did when you replaced the PCM. It seems to me that you disturbed something. I would look close at the relay center for a disturbed connection at the fuel pump relay. What did you take apart to get at the 20 pin connector?, did you move the PCM? You say you probed the engine harness side, meaning the TRANNY SIDE?, probing the TRANNY SIDE of the connector is OK, but not the other side, soe I am confused by your statement. You didnt use an ohm meter? 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 November 30, 2012 Report Share Posted November 30, 2012 For future reference, DEAD means NO CRANK, then the question is HOW DEAD, dash lights, dim on start, etc If the engine cranks its not dead, it CRANKS but does not START 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...
mrmossif Posted November 30, 2012 Author Report Share Posted November 30, 2012 I probed the engine harness side. It was in the flow chart but I probed other terminals that I should not have probed. I did also use an ohmmeter. I went over everything AGAIN and found a blown ecs fuse. The car is running fine again. Back to my original problem of the P0717 input speed sensor. On my scanner it shows that its working but after running for a while it doesn't show any rpm, if you hit the gas you get a reading but then it goes dead again. Every time I disconnect the tranny harness the plug has fluid in it. I used like 3 cans of cleaner to clean it up and it still comes. Do I have a bad iss sensor? Does the tranny fluid have anything to do with affecting the reading? And how is the fluid getting there? The harness that comes out of the tranny is dry. When you unplug the connector on the tranny side the plug is wet at the prongs and then it runs into the engine harness side and fills the plug up and runs into the wire loom of the harness. Is it possible that the fluid is going into the casing of the wire and coming out the other end? In that case I would have to buy a new harness. I don't want to get involved with this job to have missed diagnose it like my ecs fuse LOL. Thanks. Link to comment Share on other sites More sharing options...
BodybyFisher Posted December 3, 2012 Report Share Posted December 3, 2012 I replaced my ISS sensor on my 96. Tranny fluid leeches down the wires and into the plug and the harness needs to be replaced, I didnt replace mine and I should have. Once I replaced my ISS sensor, that code went away. While I was there I replaced the pressure solenoid and TCC solenoid, I should have replaced the harness and sprocket thrust bearings also as the outer bearing looked overheated. I am not sure what is wrong with your ISS sensor but someone developed an amplifier to amplify the signal. The ISS sensor is basically a pick up that reads on/off signals from a reluctor and I guess overtime its ability to do so dissapates. Here is a link to my ISS sensor replacement, http://caddyinfo.ipbhost.com/index.php?showtopic=13481&st=15&p=104122&hl=p0717entry104122 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 December 3, 2012 Report Share Posted December 3, 2012 I dont know if this works but here is the info on the ISS signal amplifier for your info, Mike http://caddyinfo.ipbhost.com/index.php?showtopic=38121&hl=amplifier 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...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.