no MPH on scanmaster Digital dash guage ok

[Tampa T-Type]

Just did some motor work and the Scanmaster will not show MPH, Aftermarket Gnx dash guage works fine. I changed the chip with a trasher 93 after trying another chip that the timing was to high. Both chips had this problem the old 28 lb chip worked fine before I got into it. Any idears where this is hooked into the Ecm?

 

[TurboBob]

The ECM receives MPH information from the stock speedometer. When you changed to the aftermarket dash, there should have been a pulse generator that went on the speedo cable that you wired into the harness so the ECM would receive pulses....

Bob
(The scanmaster gets all its data from the ECM, if you are not getting a MPH reading, it is because the ECM is not getting it.)

 

[Ormand]

And that would mean that anything the ECM does that's speed related- is not being done.

 

[Tampa T-Type]

What effect would this have on the car!

How would this effect my operation?