Unknown Driver Issue
it is a 2003 sport utility.
good to know the model we're working with✔️
im gonna grab replacement batteries for it tomorrow, dont think they’ll fix it but gonna give it a shot.
it's worth getting a suspect battery checked with a proper battery tester, this could save some $$ and time, if it's bad you have a possible cause.
i checked both of those body grounds and cleaned them up and made sure to tighten them good and im still getting the same issue.
the key thing is to measure the electrical resistance to ground as this is what the modules need plus there could be a cable issue somewhere else.
Where exactly is the EBCM located so i can try and pull that and check for corrosion. on another note of that topic, i did repaint the rear bumper and had unplugged the trailer harness could that be causing my issue aswell? i’m gonna plug it back in tomorrow as see but wondering if that isn’t my issue.
the EBCM is located externally and roughly underneath the driver's seat, very much doubt you'll want to remove it as all the brake lines go to it. This ongoing forum thread is dealing with related issues
i’m also gonna try a different battery and see if that helps my issue or not.
there are some really good and cheap automotive battery testers out there such as , they are so smart and much, much more than a voltmeter and take the guesswork out of battery checking, every Hummer owner should have one!
the only aftermarket objects i’ve installed are new LED’s all around including headlights, markers, i left the turn signals alone, and the cab lights.
👍
all the items i listed that don’t work worked previous to this unknown driver issue, all besides the heated seats that never worked when i got it.
👍
where would that 6 way IP connector be to check that aswell? it has been removed i know that, just never really went looking for it.
fyi watch
thanka for the reply gonna give these a check and see where it leads me.
hope you fix it👍
good to know the model we're working with✔️
im gonna grab replacement batteries for it tomorrow, dont think they’ll fix it but gonna give it a shot.
it's worth getting a suspect battery checked with a proper battery tester, this could save some $$ and time, if it's bad you have a possible cause.
i checked both of those body grounds and cleaned them up and made sure to tighten them good and im still getting the same issue.
the key thing is to measure the electrical resistance to ground as this is what the modules need plus there could be a cable issue somewhere else.
Where exactly is the EBCM located so i can try and pull that and check for corrosion. on another note of that topic, i did repaint the rear bumper and had unplugged the trailer harness could that be causing my issue aswell? i’m gonna plug it back in tomorrow as see but wondering if that isn’t my issue.
the EBCM is located externally and roughly underneath the driver's seat, very much doubt you'll want to remove it as all the brake lines go to it. This ongoing forum thread is dealing with related issues
i’m also gonna try a different battery and see if that helps my issue or not.
there are some really good and cheap automotive battery testers out there such as , they are so smart and much, much more than a voltmeter and take the guesswork out of battery checking, every Hummer owner should have one!
the only aftermarket objects i’ve installed are new LED’s all around including headlights, markers, i left the turn signals alone, and the cab lights.
👍
all the items i listed that don’t work worked previous to this unknown driver issue, all besides the heated seats that never worked when i got it.
👍
where would that 6 way IP connector be to check that aswell? it has been removed i know that, just never really went looking for it.
fyi watch
thanka for the reply gonna give these a check and see where it leads me.
hope you fix it👍
Having the same issues. Just completed a frame off restoration on my 2004 H2. Since getting body back on I am having the unknown driver issue. No window locks, no 4wd switch lights, gauges dead other then rpm and tach, radio not working, dimmer switch not working, will boot up and off. Losing communication to OBD.
This hummer had similar issues a few years ago, it turned it to be the air bag module under the driver seat. Door pins were shot allowing water in. Since then i have recently replaced pins but today noticed that new module is corroded again on the outside but pins are clean so I'm thinking it's different cause this time but you should check that module in your case.
tomorrow I plan to check the splice pack under the driver dash near the kick. Remove wire one by one until issue stops. Maybe check for other signs of water damage near bcm. Mine has a aftermarket radio i may also disconnect. Crazy I found this forum that is up to date having the same issues. Hopefully we can find the root. Looking forward to your updates as I will do the same
This hummer had similar issues a few years ago, it turned it to be the air bag module under the driver seat. Door pins were shot allowing water in. Since then i have recently replaced pins but today noticed that new module is corroded again on the outside but pins are clean so I'm thinking it's different cause this time but you should check that module in your case.
tomorrow I plan to check the splice pack under the driver dash near the kick. Remove wire one by one until issue stops. Maybe check for other signs of water damage near bcm. Mine has a aftermarket radio i may also disconnect. Crazy I found this forum that is up to date having the same issues. Hopefully we can find the root. Looking forward to your updates as I will do the same
The OP likely has multiple issues..
The hint is hitting the pothole. Check that wheel ABS sensor and wiring.
Next, dry the F’ing carpet mushroom farm out, LOL! Or every connector will corrode.
Next, replacing or testing with a battery (pull from another vehicle if you have to) is where I would be looking next. Run your battery into a store for a load-drop analysis, usually free. Then you at least know that variable is handled.
Now a potential biggie. Aftermarket LED lights. How many times on this forum in the last, oh say, 20 years have we seen these causing issues. Strip them out and see if that fixes anything.
That would be a good starting point.
The hint is hitting the pothole. Check that wheel ABS sensor and wiring.
Next, dry the F’ing carpet mushroom farm out, LOL! Or every connector will corrode.
Next, replacing or testing with a battery (pull from another vehicle if you have to) is where I would be looking next. Run your battery into a store for a load-drop analysis, usually free. Then you at least know that variable is handled.
Now a potential biggie. Aftermarket LED lights. How many times on this forum in the last, oh say, 20 years have we seen these causing issues. Strip them out and see if that fixes anything.
That would be a good starting point.
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