ABS Light With No Codes

[MassHoe04]

Just got a a 2004 Tahoe Z71. Approx. 194k miles. Needs rocker panel replacements (planned for tax refund next spring).

Runs smooth as butter and LOVE it!
I have a single CEL/code for B2S2 Oxygen Sensor, but no other codes and runs fine otherwise.

Every time I get up to 55+ MPH on the highway, the ABS flashes/chimes and stays on for a bit, then keeps repeating the annoying cycle until I get below 55 MPH again.
As soon as I get below 55, the light goes off and stays off. There are no codes related to ABS on the scanner. Driving around town, no ABS light or chime at all driving less than 55 MPH.

Does this sound like the old corrosion under the ABS sensor issue? Given what I have described, what are the odds of any sensor actually being bad?
I will try cleaning the hub under the sensors and see if that clears the issue on the highway, but wanted to see what you all thought.

Cheers!

 

[afpj]

Stupid question, but you sure your scanner can read abs codes? If you can see live data, track the sensor speeds at each wheel as you go above 55 see if one or more read incorrectly. Cleaning under the sensors is a cheap start otherwise. Smarter people should chime in.

 

[swathdiver]

I think the flashing light is related to the O2 sensor. Fix it and see.

 

[MassHoe04]

I think the flashing light is related to the O2 sensor. Fix it and see.

Thank you for the reply.
But, the CEL is on and stays on all the time. That is for the one code that is for the bad O2 sensor. P0159. That is the only code that is present.

The ABS light never comes on at low speed. It comes on, the light flashes and chimes, then stays on for a stretch and repeats the annoying cycle the whole time I am moving at 55+ MPH on the highway. Drop down below 55, no ABS light no ABS chime. No ABS codes stored. My scanner does read ABS codes, but nothing there. My mechanics professional scanner also found no stored ABS codes to exist anywhere in the system.

 

[swathdiver]

Thank you for the reply.
But, the CEL is on and stays on all the time. That is for the one code that is for the bad O2 sensor. P0159. That is the only code that is present.

The ABS light never comes on at low speed. It comes on, the light flashes and chimes, then stays on for a stretch and repeats the annoying cycle the whole time I am moving at 55+ MPH on the highway. Drop down below 55, no ABS light no ABS chime. No ABS codes stored. My scanner does read ABS codes, but nothing there. My mechanics professional scanner also found no stored ABS codes to exist anywhere in the system.

There's no ABS codes because it is not an ABS problem, fix the O2 sensor and watch what happens.

 

[MassHoe04]

There's no ABS codes because it is not an ABS problem, fix the O2 sensor and watch what happens.

OK. Thank you. I will be replacing the O2 sensors on Bank 2.
Just confirming what you are saying... A bad O2 sensor can cause the separate ABS light (below the check engine light) and ABS alert chime to come on at high speed only, even though they are supposed to be monitoring completely separate systems?
Thanks again for your information.

 

[MassHoe04]

There's no ABS codes because it is not an ABS problem, fix the O2 sensor and watch what happens.

Did that same thing happen to you? Just wondering... I'd be thrilled, if I could resolve the ABS light/chime issue just b replacing a failing O2 sensor.

 

[afpj]

Since you have to fix the O2 sensors anyway (recommend always do in pairs), like swathdiver said, see what happens. These vehicles have quircky electrical issues. Still, think checking wheel speeds off the 4 sensors is an easy diagnostic as well. Let us know what you find

 

[MassHoe04]

Since you have to fix the O2 sensors anyway (recommend always do in pairs), like swathdiver said, see what happens. These vehicles have quircky electrical issues. Still, think checking wheel speeds off the 4 sensors is an easy diagnostic as well. Let us know what you find

OK. I should be getting to the O2 sensors on Bank 2 tomorrow. S2 is throwing the the code on that side, but I will replace the upstream S1 on that bank as well. I'll let you know.
I just switched over from an 05 Jeep Rubicon, so I am no stranger with vehicles having their own quirks (LOL)!

 

[afpj]

By pairs, I think most people generally mean both bank 1 and bank 2 postcat or bank 1 and bank 2 precat.