Hi Guys, Thanks for getting me in the right direction. There's more to the injector signals than at first tought... and like James said there is a lot of info in the current waveform. The breakout box will be useful but not the way I was thinking in the beginning, it will be convenient in some cases to get all the injector signals accessible as getting to the connectors is a pain. thanks Luis On 1 Mar 2015 22:13, "Luis Moreira" wrote= : > Hi James, > Do you have any links that show what you mean? When you talk of rise time > is that at switch on? And peak current the same? > There are LEM products that measure DC, I use them all the time at my > current job. > Best Regards > Luis > On 28 Feb 2015 17:56, "James Holland" wrote: > >> > From: Luis Moreira >> > Subject: RE: [EE] Injector Testing >> >> > Hi James, >> > Not quite the question I was asking, I have access to plenty of tools >> like >> > that one at the moment. In fact I use one like that from fluke all the >> > time, I also have some tektronix ones. >> > I am more interested on the manner of the testing. >> > I deal mostly with 4 cylinder vehicles and although I intend to expand >> this >> > test setup to 6,8 or even 12 cylinders, this is ideal to get the >> > measurements into a four channel scope, which will show the four >> injector >> > signals and timing in relation to each other. In my opinion in one go = I >> > could get quite a lot of info just from this. The breakout box would >> allow >> > me to observe the injector signals with them still connected to the ec= u. >> > Observing the current would also give me info on injector resistance a= nd >> > any other issues. >> > As an example, I am looking at a Vauxhall Vivaro, which had a confirme= d >> > faulty injector changed. After they changed it, the problem is still >> there >> > and instead of a cylinder X miss fire I get a intermitent injector >> control >> > short circuit fault. I suspect the bad injector may have damaged the E= CU >> > output driver stage/current sensing circuit, but before I send the ECU >> for >> > repair I need to reassure myself that the rest of the circuit >> > (wiring,connectors and injectors) are fine under load, Now getting to >> the >> > injectors on a van like this is a pain and I only want to remove all t= he >> > bits to get to them a couple of times. With a breakout box I would get >> all >> > the info at once. >> > As I haven't found any setup like this I am just wandering if this as >> worth >> > while thing to persue. >> > Thank you. >> > Luis >> > On 27 Feb 2015 18:10, "James Holland" wrote: >> > >> >> The breakout box is a good idea but I don't see a big advantage of havin= g >> multiple current probes. It should be pretty easy to spot a bad injector >> from its current waveform if its an electrical failure rather than a >> blockage; the peak current and the rise time tell you all you need to kn= ow. >> The LEM sensors that I've looked at measure AC current only, if you do >> decide to build a setup then sensors that can measure the DC component a= s >> well would give a better representation of the waveform. >> James >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .