64caddyuk Posted June 15, 2010 Report Share Posted June 15, 2010 I have a 2000 cadillac deville dhs and I am having problems with the speeedometer - it does not move at all - just sticks at 0. Also the odometer and cruise dont work either. I have hooked a obd2 tool into it and drove it around and the speed shows fine on this...So next I tried disconnecting the VSS sensor wire from the sensor on the output shaft - then drove it with the obd2 tool and it now does not show the speed on it - so I guess it cant be anything wrong with this sensor...I also pull no DTC codes/check engine not on an have driven 20-30 miles and still no light - but no speedo either! I wonder whether it is the input shaft speed sensor (think thats what its called!) but I would of thought that would thrown a code up? Please can anyone help? Please!! Thanks Paul. Link to comment Share on other sites More sharing options...
BodybyFisher Posted June 15, 2010 Report Share Posted June 15, 2010 There is a VSS sensor and an ISS sensor, if the ISS fails, the PCM will use the VSS as a reference for transmission shifting with a default line pressure. The ISS should have nothing to do with the speedometer It is odd that you dont have any codes. Your test of the VSS seems valid. It is possible you have having a problem with the IPC 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...
64caddyuk Posted June 15, 2010 Author Report Share Posted June 15, 2010 Thanks for that 'bodybyfisher' haha sweet name. Okay so Im crazy glad that the iss can't be the problem if you say it don't have anything to do with the speedo...But its still a mystery as to why it aint working. I thought that too about the IPC so Ive studied the wiring diagrams on alldatadiy and in my haynes - but it looks to me like the speedo runs off of the same wire thats spliced to the cruise and rear impact sensor - so you would think that they would log faults if they arent getting the signal correctly ? The cruise dont work either and it seems to get its speed signal from the same wire as the speedo - coming from the vehicle speed output on the pcm . Basically Imn wondering could it that the PCM is bad? Anyway of testing the output from the Speed output wire from this??? Or am I even right in assuming this??? Thanks!!!! Link to comment Share on other sites More sharing options...
Papalac Posted April 30, 2017 Report Share Posted April 30, 2017 I am also having speedo not working problems with a 2002 Eldorado-just replaced vss and no luck-fuel gauge also not working-cruise and odometer not working-and mph led brightness fluctuates-just bought car for cheap and trying to fix up-would also like to know how to test output signal wire from pcm for speedo-just getting into this project and would like to know any good web sights to find flow charts for sensor troubleshooting Link to comment Share on other sites More sharing options...
Bruce Nunnally Posted April 30, 2017 Report Share Posted April 30, 2017 @Papalac Bruce 2023 Cadillac CT4-V Blackwing Follow me on: Twitter Instagram Youtube Link to comment Share on other sites More sharing options...
Papalac Posted May 3, 2017 Report Share Posted May 3, 2017 Figured out speedo problem-both wires inside of the sensor plug had been pulled on and broken inside of the plug-soldered wires and good to go-now have to attack a p0300 current code problem-gotta love wiring problems! Link to comment Share on other sites More sharing options...
BodybyFisher Posted May 5, 2017 Report Share Posted May 5, 2017 On Wednesday, May 03, 2017 at 7:26 PM, Papalac said: Figured out speedo problem-both wires inside of the sensor plug had been pulled on and broken inside of the plug-soldered wires and good to go-now have to attack a p0300 current code problem-gotta love wiring problems! Thanks for looping back on this and letting us know what it was. The VSS sensor correct? 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...
Papalac Posted May 5, 2017 Report Share Posted May 5, 2017 Not so there bbf-I did change the vss but probably for nothing -my best guess is that someone had pulled hard on the harness at the sensor and pulled the wires apart down in the connector-I foolishly listened to the guy that i had bought the car from and changed the sensor-trust but verify! Link to comment Share on other sites More sharing options...
BodybyFisher Posted May 5, 2017 Report Share Posted May 5, 2017 42 minutes ago, Papalac said: Not so there bbf-I did change the vss but probably for nothing -my best guess is that someone had pulled hard on the harness at the sensor and pulled the wires apart down in the connector-I foolishly listened to the guy that i had bought the car from and changed the sensor-trust but verify! I wasn't clear, it was the wires at the VSS connector? 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...
Papalac Posted May 6, 2017 Report Share Posted May 6, 2017 Correct,it was inside the sensor connector where you can't see-I have another one for the discussion-on the same 2002 eldorado i am getting a p0300 dtc on the onboard diagnostics and a p0302 on my handheld scanner-flashing check engine light-how can I get two different codes? Link to comment Share on other sites More sharing options...
BodybyFisher Posted May 6, 2017 Report Share Posted May 6, 2017 Thank you for the VCC feedback. Were you getting a VSS code when the wires were messed up? As you know P0302 indicates a problem with cylinder #2. However, the 2000 has a coil pack cassette and they have been known to crap out. @Logan has had experience with the cassettes and may know why you get P0300 and P0302 together, it may be a feedback due to the 302 misfire causing a non descript misfire (300). Logan has stated that he kept a spare cassette in the trunk. If you can find a known good unit and swap it in you can help your diagnosis. My guess is you need a new coil pack 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...
Logan Posted May 6, 2017 Report Share Posted May 6, 2017 On a 2000.....technically there is no such thing as a p0302 code. Go look it up in the GM service manual for MY2000 Deville. On a 2000....what you do get is p0300. The p0300 requires you to connect a GM Tech 2 and look at a misfire graph to determine which cylinder is misfiring. Some aftermarket scan tools have reverse engineered the data....and created the misfire code p0302....or 303..or 304 etc to identify the misfiring cylinder. So p0302 would indicate a #2 misfire. So....the car is telling you p0300. The aftermarket scan tool is telling you p0300 and it's own made up 'p0302'. Logan Diagnostic LLC www.airbagcrash.com www.logandieselusa.com www.ledfix.com www.ledfix.com/yukontaillightrepair.html www.ledfix.com/ledreplacements.html www.ledfix.com/j42385toolrental.html Link to comment Share on other sites More sharing options...
BodybyFisher Posted May 6, 2017 Report Share Posted May 6, 2017 Thanks @Logan are the coil packs swappable side to side to see if the misfire follows the coil pack? My guess is that it would create a P0301 on the other side, or because it is flipped it becomes a P0307? I would replace the plug in #2 and see of that solves the misfire. Its not advisable to pull the plug, inspect it, regap and reinstall, the plug threads are encapsulized with anti-seize that is disturbed upon removal, so a new plug is the way to go. If the misfire is still present, depending upon what Logan says about swapping coil packs, replacing it with a "known good" coil pack would help find the 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...
Papalac Posted May 7, 2017 Report Share Posted May 7, 2017 Thanks for all the input-I have pretty much guessed that something like what logan had described was going on-I ran an old plug wire and plug off of number 2 on front cassette ,grounded the plug,disconnected harness from rear cassette and found no spark on that cyl while cranking over engine-had spark on all of the other 3 when I did the same thing-probably the cassette Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.