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pavetim
June 12th, 2012, 05:19 AM
I was looking into making a bench harness. All the ones I seen uses the OBD connector. Now my question is I have a spare cable for my V2 that goes from the OBD to the CAT5 I think. The OBD2 part is cracked. Why can't I cut that end off so that I can build a harness and just plug right into my V2 using the CAT5 end? Also as far as the 12V is concerned. Can I use the switched and unswitched from the same source? I like run one wire from the battery in my harness but then split if off into two wires which one is hot and one has a switch? Or do they have to be from different sources?

Blacky
June 12th, 2012, 08:06 AM
Yes, you can wire it all up directly.

The power that goes to FlashScan is un-switched, so you can turn the PCM's ignition (switched wire) on/off without causing FlashScan to lose power.
The PCM will have at least two 12V connections, one switched and one unswitched.

The wiring diagrams are in the bench harness tutorial on our web page
http://download.efilive.com/Tutorials/PDF/Bench%20Harness%20Tutorial.pdf

Regards
Paul

pavetim
June 12th, 2012, 08:44 AM
Ok Blacky I think I got all that. Is the reason for the switched and unswitched to the PCM the same concept as when your done flashing and turn key off to let the flashscan countdown for 15 seconds? So bench flashing when it's done flashing you would just turn switched power off, and then begin countdown?

Blacky
June 12th, 2012, 11:31 AM
Ok Blacky I think I got all that. Is the reason for the switched and unswitched to the PCM the same concept as when your done flashing and turn key off to let the flashscan countdown for 15 seconds? So bench flashing when it's done flashing you would just turn switched power off, and then begin countdown?

Yes. After you switch off the ignition, the PCM does some housekeeping and updating of its internal memory, so it needs power even after ign-off.

Regards
Paul