Dash symbols but no problem

2007 GMC ENVOY
115,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
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STEVE620
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Every now and then 4 dash symbols light up for a short time then go off. It was happening every other day, but it has not come on for about a week. I'm not getting any codes and everything seems to working okay.
Jul 11, 2020 at 12:07 PM
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STEVE W.
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With all 4 coming on it is likely you have an issue with one of the ABS wheel speed sensors.
If there is a fault in one it will turn off the ABS/Traction control and turn those lights on. What are you using to read the codes? If the lights come on there will be a stored history code at least, however it may not show up on some tools.
Jul 11, 2020 at 6:31 PM
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STEVE620
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I"m using Blue Driver reader.
Jul 15, 2020 at 12:13 PM
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STEVE W.
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Okay, that should be able to read the ABS module, at least they claim it will. GM had had an issue with the front ABS wiring failing and turning the lights on. What you might try would be to have someone set in the truck while you go along the wiring harness from the sensor to the frame and along the frame doing a wiggle test. You just move the wire around and gently tug on it and the connectors. If the lights come on while you are doing the test you have found the culprit.
Jul 15, 2020 at 1:20 PM
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STEVE620
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thank you will try that.
Jul 15, 2020 at 2:00 PM
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STEVE W.
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Good luck, please keep us informed if you find the problem. Intermittent faults can drive you batty searching.
Jul 16, 2020 at 5:22 PM
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STEVE620
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I did what you said with the wires but nothing. it has been about 2 weeks now and no lights. if it should happen again will stop car and do the same.If the sensor was starting to go bad would this happen?
Jul 16, 2020 at 5:27 PM
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STEVE W.
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Not usually. This is a common issue with wiring though. It will come and go with no real cause. Hit a bump and the lights come on, hit the same bump and no lights, turn left and they come on, next time they don't. I would keep the scan tool in the truck, if they come on, try to get any codes or better yet look at the live data for the ABS speed sensors, say you are moving at 30 mph, they all should read the same, if you have one that reads 15 or zero, that is the corner to look at.
Jul 16, 2020 at 6:30 PM
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STEVE620
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I just found the problem, it turns out that the Body Control Module (BMC) was doing some crazy things. I took the car to a GMC Dealership to check out. They told me that there is nothing wrong with the BMC. I have a Dash Cam in the vehicle and I was getting power for it from the OBD2 port , I purchased this cable from Amazon. I removed the cable, after a day of driving the car the radio started to play again, then the dash lights went out. Now all is good. GM told me that this is a known thing to happen when you use the port that way.
Oct 5, 2020 at 5:09 PM
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STEVE W.
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Thanks for the update. That is a different find, I wonder if the camera uses the port for more than just power, does it capture things like time date speed and braking events? That could explain why it was causing problems. If it was only getting power then it would likely plug into the power socket.
Oct 5, 2020 at 5:45 PM
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STEVE620
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The camera only get power from the port.
Oct 6, 2020 at 2:59 AM
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STEVE W.
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Strange. The OBD port uses the same power feed as the lighter, unless there is some type of feedback on the ground side. Keep us posted if the issue stays gone or returns. Thanks again.
Oct 6, 2020 at 7:46 AM