DLC 4&5 Voltage
Hello every one,
I am trying to collect a fair amount of data samples to get a average voltage between Pins 4 and 5 at the DLC KOEO and KOER. I usually test between these pins when diagnosing problems as part of my routine.
In an attempt to teach this method I would like more information than I can gather on my own. I am willing to share the data collected here. Let me know if you have any questions! I will add more manufactures if needed, select GM if not listed and make a note and I will adjust form.
Thanks in advance for any contributions.
Should I choose 'Option 10' for the make? There's not a choice for Subaru. KOEO is 0.45 mv. No activity on CAN.
Well ideally and from a how it should work on from the vehicle-side: 1) pin 4 is chassis ground (for sourcing power to external equipment), and pin 5 is signal ground (for communication lines). 2) There could be non-zero voltage readings between pins 4+5, but it is going to depend on hardware equipment installed in the vehicle (ECU options, etc) and the operational state of the communication…
Hello Bernie, I am mainly curious to see if similarities will arise across specific makes and models. I am expecting that to be the case. I have been doing a DLC quick testing seminar and thought it would be helpful to back up what I am saying with some data collected by some one other than myself. If a specific model has a few "known good" values of 0.150V and another model has .005V I am…
Brian, totally get where you are coming from, and dig the effort. Keep in mind that measurements should be done directly off the face of the DLC, otherwise the measured value may get altered by the presence of any active components that are inside any attached external test equipment. I know accessing the DLC face is a pain, but for good measurements its necessary. Again, totally like your…
Bernie, I see what you are saying, and have thought a little about the differences in testing methods, possibly even the test leads being dirty causing incorrect readings due to we are looking for differences <1 V, or using a BOB. If others care to participate I hope to see if trends will appear early on. We will see what happens! Thank you for your input.
Hi All, Bernie is spot on. As I have found in the field, different OEMs have different connectivity to these pins, even between models. Also, many tools connect these two pins together internally, which would tend to negate any "open circuit" readings. Cheers, Bob
Hi Bob, I don not think that I was clear about the "why" of doing this. I am aware that many tools, mainly after market, connect or bridge 4 & 5 . I know that differences exist between models and manufactures as well. I am gathering this information due to the fact of going through my own diagnosis of vehicles at times I get a reading between 4 and 5 that seems high based on my experience…
Bernie, isn't the use of a DLC BOB the same as the face of the DLC? Davie
Time and scheduling permitting I will try some of this tomorrow
Have you seen this site, ScanShare ? I don't know if it would have any of the data you're looking for, might be worth a shot. scanshare.io/Home/Register
I have not seen that site. I am taking a look at it now. Trying the $5 Sub
Oh, wow, you hadn't seen ScanShare.....If I remember the story correctly Jim Wilson's son wrote the code for the site so Jim could share info with other techs and teach Data analysis better. He's an instructor with Standard now.
It's great for educators and long-distance tech assist. You can upload from many different tools, and then anybody who reviews the data can customize the list any way they want. And the best part, since it is web browser based, it works on any Mac too. Even my old one that won't play videos for THIS web site. :-)
UPDATE Please convert reading to Volts. IE 6.2mV = 0.0062 V Here are the results so far. Who ever had posted the 96 Suburban I am assuming readings are in mV and will change to volts. Thanks for everyone who is taking the time to add! If nothing else we will all be familiar with what to expect between 4&5.