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Ok I did do some research here in the forums but I didn't see anything that matched my situation, so hopefully, you guys can help me out. First, let me describe my setup:
I have replaced my stereo with a different system and have 2 amps wired in
I have completely replaced all of my cigarette lighters with USB ports (one of which goes directly to my stereo) and my fuse for the cigarette lights is not blown
My scanner works with all of my other vehicles but my 01 C5
I took it to both Oreilly's and Autozone and neither of their scanners could connect with my computer
When I take it to the shop to get my inspection done, the state computer connects to it fine and is able to read all of my monitors
See if you have power to pin 16 on the DLC…where your scan tool hooks up to…it should have power at all times !!..just because the fuse isn’t blown doesn’t mean you have power to pin 16…also make sure that pins 4 and 5 have a good ground (12 volt test light connected to power and tip of test light to both those pins…should be a bright light…you may also have an intermittent data bus issue.
My personal one is a centech from harbor freight, but the one that O'Reilly's had was an Innova I believe. I don't recall the brand from Autozone. All 3 of them wouldn't communicate though with my car though. I just don't understand how the shop one can communicate with it and the others can't.It makes no sense to me :/
As I had mentioned it may be an intermittent data bus issue and see if you have 12 volts on pin 16…if you can’t communicate check pin 2 on the DLC…you shouldn’t see 12 volts or ground on it…with key on with a scope or graphing multimeter you would see a 0-7 volt square wave…with a DVOM you should see .2 to .3 volts that will be fluctuating….with the data line shorted to B+ or ground you will not be able to communicate with the scan tool.
C5 Diag: So I took it back to the shop to see if I had cleared any of the monitors enough to pass inspection and once again the state inspection system had no issues talking to my car via the DLC. When we got done, we hooked up the shop's scanner (Blue Point EECR1B) and it connected with no issue and gave a matching reading as the inspection system for the monitors that weren't ready. I came home and tried my cen-tech scanner and of course, it didn't connect I haven't gotten to testing all the voltages yet, thanks for all of your suggestions on troubleshooting.
So I called their tech support last night and the first time I tried it didn't connect. I started my car and tried several more times and it finally connected I have no idea why. Sigh. I does show all of the same monitors as not ready. :/
So I called their tech support last night and the first time I tried it didn't connect. I started my car and tried several more times and it finally connected I have no idea why. Sigh. I does show all of the same monitors as not ready. :/
Did you check pin 16 ??…these DLC connections sometimes are faulty…don’t know which monitors are not ready but pending or current DTC’s will keep the monitors from running.
I did check it yes and it was working. This is clearly an intermittent issue as I could get it to connect multiple times but only after it repeatedly failed. What's also interesting is I never unseated it or adjusted it once I physically connected to the port, it just miraculously started to work after several attempts to start the test. At least I know I can eventually get it to connect. Thanks for all of your help C5 Diag!
I did check it yes and it was working. This is clearly an intermittent issue as I could get it to connect multiple times but only after it repeatedly failed. What's also interesting is I never unseated it or adjusted it once I physically connected to the port, it just miraculously started to work after several attempts to start the test. At least I know I can eventually get it to connect. Thanks for all of your help C5 Diag!
Best to buy a set of these “terminal tension” kits to check for any loose connections on the car…it is also called a “drag test”…each terminal should have the same amount of drag when inserted and removed….you may be able to tighten one that’s loose.
Scanner communication error
I haven't gotten to testing all the voltages yet, thanks for all of your suggestions on troubleshooting.
