Went for a drive today..first time in a couple of weeks and noticed the speedometer wasn't working. Anyone else have this problem? Any leads on a fix. Car Details: SVS Twin Turbo, AEM, stock gears-no speedo correction box, other stuff. No changes to the tune, no mechanical changes, checked all the fuses (i.e. under dash, left side engine compartment). I'm not very familiar with these cars and wanted to see if there are a few quick things that I could check.
Speedometer Probelm...help needed
- Thread starter Earl_H
- Start date
V10SpeedLuvr
Enthusiast
Bad speed sensor? But I think that would throw a check engine code. Atleast it did on a buddy's Mustang
Ulysses
Enthusiast
You've got an AEM in there. You should be able to hook up to it and see if it is outputting an mph.
On my 95 (setup is a little different than yours) I thought it was my speed sensor but it wasn't. I had to replace the Ignition Control Module.
Take it to a good ViperTech, they have a diagnostic process and can narrow it down for less than $100. Then you can decide how you want to fix it. I replaced my ICM myself because it only took 2 minutes and I saved alot.
Take it to a good ViperTech, they have a diagnostic process and can narrow it down for less than $100. Then you can decide how you want to fix it. I replaced my ICM myself because it only took 2 minutes and I saved alot.
PhoenixGTS
Enthusiast
As you look at the PCM, on the middle of the three big conenctors, pin 27 (white with tan tracer) is the signal from the speed sensor to the PCM, but pin 28 (white with orange tracer) is the wire from the PCM to the speedometer. Check pin 28's wire (bottom right hand wire) to make sure there is not something easy like a mechanical injury to the wire (perhaps someone tapped into it previously and the patch has failed?). The "covers" on the big PCM plugs pop off so you can look in there without unplugging the big plug. Just a place to start.
GoCanes1
Enthusiast
Have you changed out your radio lately? The stock radio is connected to the speedometer and changing the radio could possibly short out the speedo.
ROCKET62
Has Left the Room!
Please elaborate.
Joe Dozzo
Enthusiast
Hello Earl,
Car used to have 3.45 gears and a speedo box. I remember jumpers from speedobox into PCM, but not any splices - but then I did not do either the install or removal.
Did notice once when THOROUGHLY cleaning engine bay I must have gotten some water / cleaner someplace it shouldn't have been because that caused the speedo to read 80 - 90 mph with the key on but the car not moving. Behaved normally after a day drying out at the drag strip.
Car used to have 3.45 gears and a speedo box. I remember jumpers from speedobox into PCM, but not any splices - but then I did not do either the install or removal.
Did notice once when THOROUGHLY cleaning engine bay I must have gotten some water / cleaner someplace it shouldn't have been because that caused the speedo to read 80 - 90 mph with the key on but the car not moving. Behaved normally after a day drying out at the drag strip.
GoCanes1
Enthusiast
The stock radio has a wire that is connected to your speedo to raise the volume as you accelerate. I changed my deck out and the install company shorted the speedo out. Happened to Baz in the UK also.
Joe Dozzo
Enthusiast
Hello Earl,
Right up front by the PCM. If I remember correctly, the box was attached on the right (as you look at it) side of the housing containing the PCM with double sided tape.
Joe
Right up front by the PCM. If I remember correctly, the box was attached on the right (as you look at it) side of the housing containing the PCM with double sided tape.
Joe
GoCanes1
Enthusiast
I did, it completely burnt it. If you make sure that the installer discontects that wire before you start the car everything will be okay. I think Baz just needed the wire diconnected and then his worked again.
Joseph Dell
Enthusiast
Remember that the AEM takes a vehicle speed reading as well. See if the AEM is putting out the correct speed. If it isn't then it sounds sensor related.
JD
JD
Joseph Dell
Enthusiast
then the 'puter is fine. the wiring to the speedo may not be.
at least the sensor is working properly!
at least the sensor is working properly!
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