M5 Expert (>4000)
Join Date: Oct 2010
Location: Cobourg Ont
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Back probing is not easy and you will likely need a a magnifying glass and extra light. In theory it is as simple as sticking you digital volt meter probe in the harness that plugs into the DME. The problem is lack of room and multiple rows of connectors. For me the hardest part is finding the correct pin, bad eyes. Most people have a problem actually making and keeping contact on the pin. One thing you need is an alligator clip that slides on to the probe. If you are testing grnds you can clip it to positive if testing positive you clip it to a grnd. That frees up at least one hand but cuts frustration by 3/4s.
Not everyone would do it this way because it has issues. I made up another tool with the other alligator clip as they come in packs of two for your meter. I soldered a straight pin on it so instead of struggling to hold the probe in a confined area I simply pull the DME look at which pins I need to probe and find which wire that is and put a big piece of masking tape on it with notes. I then put every thing back and start up the car and push the pin right through the wire and it holds by itself so I can do other things including hold the meter so my old eyes can read it easier.
Maybe you are asking which pins to probe? they can be found in the WDS but if you are having issues I can look those up and post the diagrams and pin outs.
Last edited by Sailor24; 24th December 2016 at 02:51 AM.