speed odometer not working
wyodan59
06-10-2015, 04:59 PM
Hello. This Grand am is a 4cly 4speed trans. My daughter is off to school. She called and told me her speed odometer is not working. She also mentioned that it is not shifting properly if at all. Is the speed odometer operated by cable? Would the two be related to the transmission going bad?
Thanks Dan
Thanks Dan
GTP Dad
06-14-2015, 10:46 AM
There should be a speed sensor located on the outside of the transmission. This has probably gone bad and needs replaced. It is not a hard job. Since you didn't state what year I am assuming that it is a newer car with an electronically controlled transmission. The speed sensor issue is probably why the transmission is not shifting correctly as well.
Tech II
06-23-2015, 10:40 PM
Agree......you don't say the year.....on older cars, the plastic gear of the sensor would "apple core".....could be a bad sensor....could be a bad connection at sensor....could be a damaged wire harness from the sensor to the computer....
wyodan59
06-28-2015, 03:03 PM
Sorry for the lack of info. It is a 1996. She was 200 miles away. I went and pulled it home. I got it to shift by running it hard. When it shifted it acted like it was slipping when I let off it shifted. but the speedo stilll does not work.I am assuming it is going to have the plastic gear. Is this inside the pan or can it be accessed from outside?
Tech II
06-28-2015, 05:22 PM
The only way to know for sure is by looking at PCM data with a scan tool......you read the data from the speed sensor, and compare it to the speedometer......for example, if your scan tool reads 60 mph, and the speedometer reads zero, and you are doing 60 mph, then you have a bad cluster or open wire to it.....if the speedometer and data from the scan tool read the same, then it's the sensor, wiring, or PCM that is the problem....my guess would be the sensor or the wiring.....the sensor is located on the passenger side of the tranny, where the passenger side axle comes out....it is near the top, firewall side...you will see a harness going to it......check the harness for damage....just one bolt holds it in......pulls straight up out of the tranny...look at the gear for damage(apple coring....like someone bit the center of the apple out)....
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