scanmaster running amuck?

[kh440]

Finally got th ebeastie on the road again, that's the good news at least. Problem is without asking for permission the readings on the new scanmaster are all over the place-just for an example the mph will flash from 18 mph to 240 mph (speedo says 40-ish)..three people (including myself) have checked and re-checked the wiring and connections and all appears normal: is it possible there's something screwy in the unit itself?

 

[87geeinn]

I would PM "TurboDave" on here or contact him over at FULL THROTTLE SPEED - Store Front Page

 

[kh440]

was going to call Mike come Monday just curious if anyone else has had this experience

 

[aminga]

Does it have a good ground?

 

[kh440]

Does it have a good ground?

that was my first thought also-but everything "looks" kosher, and regrounded at least one extra time with the same results

 

[pacecarta]

it doesnt have a 2.2 chip in it does it ?


what does it show when you first power up ?


red - 12v switched IGN source
black - ground make sure its a good solid ground
white - data stream - pin E aldl (or splice to orange wire at backside )

http://www.geocities.com/rad87gn/tech/scanmaster.html

 

[kh440]

I have version 2.1. Regrounded it today and no change in the crazy readings in all modes...But at least I can say my car is capable of 240 mph...:biggrin:

 

[johnnyttype]

i have gotten some crazy readings like that before...knock counts in the 40's at idle and what not... it was intermittent, but often enough to be annoying! i had a good ground, a pin going to the B terminal of the ALDL for power i believe, and then a pin in the E terminal for the ECM data. when it got cold outside the issue popped up pretty often and i noticed the slightest tap to the E pin would make the scanmaster go hay-wire...so now it is spliced into the wire, not using a pin in the ALDL anymore, no more problem! hth

 

[Mike Licht]

the scannmaster is a display device, in other words it displays the data spit out by the ECM it does not make up numbers that are not there. ECM data streme problems are very common these days given the age of them. Even thought the car runs fine. You may want to check your Sensor returns at the ecm or ecm ground as well. I would suggest putting it another car or simply send it to us for testing, if someting is worng we will fix it, no problem
Mike

 

[pacecarta]

i have gotten some crazy readings like that before...knock counts in the 40's at idle and what not... it was intermittent, but often enough to be annoying! i had a good ground, a pin going to the B terminal of the ALDL for power i believe, and then a pin in the E terminal for the ECM data. when it got cold outside the issue popped up pretty often and i noticed the slightest tap to the E pin would make the scanmaster go hay-wire...so now it is spliced into the wire, not using a pin in the ALDL anymore, no more problem! hth

you cant get power from aldl port

pin b is diagnostic terminal (SES light)

you can get data and ground but not power

pin e is aldl datastream (connect SM white wire )

pin A is ground (you can connect SM black wire here)

 

[johnnyttype]

you cant get power from aldl port

pin b is diagnostic terminal (SES light)

you can get data and ground but not power

pin e is aldl datastream (connect SM white wire )

pin A is ground (you can connect SM black wire here)

ah, sorry its been a while! i knew i had two wires pinned into the ALDL, just for some reason i forgot it was the datastream and ground.... so i used A and E and ran my power wire over to the fuse box under the dash.

thanks for the correction

 

[kh440]

the scannmaster is a display device, in other words it displays the data spit out by the ECM it does not make up numbers that are not there. ECM data streme problems are very common these days given the age of them. Even thought the car runs fine. You may want to check your Sensor returns at the ecm or ecm ground as well. I would suggest putting it another car or simply send it to us for testing, if someting is worng we will fix it, no problem
Mike

Thanks Mike, I'll try swapping ecm's and scanmasters with another car and see what happens.