View Full Version : Scanmaster 2.1 problems

07-31-2009, 10:09 PM
Hey I was trying to find out whats wrong with my scanmaster when I'm driving my car under no boost my readings jump all over the place one minute it will be reading O2's the next it will jump by it's self to temp and then to MPH and then back to O2's or the face will look like this ---- ---- and it will show anywhere fro 10.0 to 57.0 degs of knock under no boost what gives

08-01-2009, 01:13 AM
under what conditions is this happening? Cold engine, warm engine?

Does it get worse if you hit the brakes?

You are getting errors in the data. This can be caused by a bad connection, or noisy data from the ecm.

The main cause of noisy data is the low speed fan relay. Its a long story, but the ECM uses a pulsing output to turn on the low speed fan relay which generates a string of spikes. Some ECM's pass these spikes thru to the datastream. Some ECMs are worse than others.

The Scanmaster has a noise filter to handle these spikes, but a really noisy ECM can still mess the data up.

So, try unplugging the middle relay on the driver's side fender underhood and see if it goes away.


(or you have a bad ground connection on your scanmaster.....)

08-01-2009, 05:53 PM
warm engine, and it's ok if I hit the brakes last night it just shut off all together on my way home from work I checked the ground and its good I'm thinking I may need a new one I got it back in 04 when I was in IRAQ

08-01-2009, 06:01 PM
no need to buy a new one, send that one in and we can check it out.


08-01-2009, 08:01 PM

08-07-2009, 01:08 AM
I've sent my scanmaster out today via UPS. I just sent it to Fullthrottle I hope thats ok?

08-07-2009, 05:10 AM
thats the right place to send it