2000 Saturn Lw2 wagon speedometer/odometer issues

[JediMasterMatt]

Hi,

I have a 2000 Saturn wagon with 153,000 miles. It has run fine for the last few months I have owned it. I used it yesterday with no issues. Today I get in and take the boys to school and realize after a mile or two down the road that my speedometer and odometer are not working. The speedometer is staying at zero, and the odometer is still reading 153,307 miles after going like 20 miles. I even put on the trip counter to see if that was moving and it was not. Any ideas what this could be? The other gages are working and the car is otherwise running and shifting fine. Please help!!!

[mattachuz]

maybe the speed sensor in the wheel or the BCM having issues, did u pull the battery for 10 mins?

[JediMasterMatt]

I did not pull the battery for 10 min, but I did notice on the way to work today that the cruise control still works.. even though the speedometer is telling me Im going 0 mph... Does this change any ideas for you?

[mattachuz]

usually the CC only works at speeds over 25 mph, if the car knows its going fast enough to engage CC I wonder why the odometer isnt working?

I SUMMON THE DUCK!!

[JediMasterMatt]

That was exactly my question as well, Mattachuz.. I couldnt understand why the cruise control would work if the speedometer is showing zero.. so I knew at that point when I engaged the CC and it stayed at the same speed as the traffic I was following, that the car knew it was going over 25 mph..
So I have no idea why the speedometer isnt working and the odometer is still reading the 153,307 miles.. I am very mechanical and have no issues doing the vast majority of my car repairs.. but I have no clue what to check..
If the car knows its going over 25 mph.. which it must in order for the cc to stay engaged... then I would rule out the speedometer sensor on the transmission.. what else is there to check?

[mattachuz]

transmission has a speed sensor? i think either the front or back wheels one of them has a speed sensor,

the IP(instrument panel) could be to blame but its really unlikely, the ODO reading is stored in the BCM and it should read on the cluster regardless.

[JediMasterMatt]

I had read somewhere else that the speed sensor was on the side of the transmission.. they could have been wrong.. thats why I came here.. I want the right info.. Do u think it could still be the speed sensor even though the car can tell it is going over 25 mph and the cc works but the speedometer doesnt? Would a bad speed sensor cause the odometer to stop at 153,307 also?

[JediMasterMatt]

On the drive home last night I again played with the Cruise Control. It works perfectly. The car runs perfectly. I have no service lights, engine lights, etc.. When I turn the key the tachometer does its normal sweep, but the speedometer needle drops a little bit below the 0 MPH mark and then goes right back to the 0 MPH mark. The Tachometer moves like normal during driving, but the speedometer and the odometer dont move. The speedometer stays at 0 mph and the odometer is still reading 153,307.. I need to figure this out.. I am going through a divorce and I need all the money I can save for my lawyer. I cant afford to drive around and get tickets because I dont know how fast Im going. Nor do I have the money to start replacing all these parts without knowing what part is bad. Is there anybody thats knows what parts I should test and how to test each part?? Please let me know...

[fdryer]

There are two speed sensors in the transmission, one for input, the other for output. The wheel speed sensors are used also for speed information. Its not entirely clear which one is causing your problem. At the least, no wheel speed sensor is faulty since you aren't getting any error code from the ABS/TC indicator - the ABS/TC light would turn on if a wheel speed sensor, wiring, reluctor or electronics fails. Presuming the wheel speed sensors are OK leaves the input/output speed sensors on the xmission.

Because the two instrument panel gauges aren't working I would go the easiest route of troubleshooting; remove, disconnect and reconnect the i/p first in the hopes that its a loose connection before going any further.

C-C works off information within the pcm that has wheel speed info. The pcm doesn't care one bit if the speedo or odo works as they are simply displays (output devices) and do not contribute to pcm operation. The pcm governs speed control when c-c is engaged. Whether the speed info comes from the wheel speed sensor or xmission output sensor is the question. I'm of the opinion that its the xmission output sensor. Try the i/p test first.

[born again]

For automatic transmission the speed is detected off a sensor in the transmission. For manual transmission the speed is detected off an ABS type sensor on the right front wheel. If you have MT and ABS then this signal must be shared (although I am not sure that this combination exists). I would suspect something in the instrument cluster or the wiring/connections, as fdryer suggested. The CC wouldn't control without speed feedback. You may have a failed instrument cluster. These can be rebuilt or you could go with a salvage part.

[JediMasterMatt]

Thank you very much for the information. I will check what you have said to check and report back with what I find. Again, Thank you all for helping with this.. I forgot to mention I have an automatic transmission.

[mattachuz]

if it is the cluster dont fret, its a easy installation! 8 bolts to get it out to be exact, i can pull mine in less then 5 mins now.

ill post exact sizing info for the bits you need if it comes to this.

[mattachuz]

well well, did you fix it yet? im just curious..

[Jonnyferrari]

I have a similiar issue, where my speedo and tach. "stick," especially when coasting from >50mph, then hop down to the actual speed. Strange, as nothing else is impaired but the dials..

[JediMasterMatt]

Well interestingly enough.. the issue went away by itself.. I was getting ready to look at all the stuff u guys said to check. I went to walmart to grab some stuff and on the way home I looked down and was like "oh Im going 60.. I better slow down" .... "wait, IM going 60" "my speedo is working" "yay"

Needless to say I was very happy and it has worked for the last 2 weeks without issue.. I wanted to wait before posting back cuz I didnt want to say "hey its working" and then have it stop the next day..

So I have no clue what it was, but it fixed itself.. I assume it was a loose wire or something..