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So you're saying, even if I purchase a scan tool, (which I did a few hors ago, Yikes!) to erase those light codes, them lights are coming back on?? Dang!
Yep. I have attached a page from the factory chassis diagnostic manual that discusses the function of the ABS warning lamp. Specifically it states:

The ABS Warning Indicator will remain lit during
every key cycle until a circuit or component fault is
repaired and the CAB no longer detects the fault.
After repair of a sensor signal fault or a pump motor
fault, the CAB must sense all four wheels at 25
km/h (15 mph) before it will extinguish the ABS and
TRAC OFF Indicators.


Bottom line: as long as a problem is still detected by the CAB the lamp will stay on. Conversely, if the problem is no longer detected the lamp will go out on its own. I know this for a fact from experience with my own van. We frequently drive some very dusty gravel/dirt roads in the Everglades. Often the ABS light will come on while we are out there. I'm guessing the dust somehow interferes with the operation of one or more of the wheel speed sensors. The light always turns off on its own as it did again this past weekend. I don't worry about it and I don't even know what trouble code is.

As far as the red brake warning lamp the same page of the manual states:

The red BRAKE warning indicator is also located
in the instrument cluster. It can be activated in
several ways. Application of the parking brake or a
low fluid signal from the fluid level switch located in
the master cylinder reservoir will cause the indicator
to come on.


This statement is somewhat ambiguous as it says the lamp is "activated in several ways" and explains two of those ways. It doesn't say those are the only ways though it kinda implies that.

Anyway, you've got the brake fluid level sensor on the side of the master cylinder and the parking brake switch that can turn on the red brake warning light. Both switches are normally open and work by grounding the circuit to indicate a problem. You should be able to disconnect either one to see whether there is a problem with that particular switch. If the light turns off when disconnected, well, there's your problem.

I took a look at the wiring diagrams to see how both of these inputs interact with the light in the cluster. The parking brake switch is directly wired to the cluster. The brake fluid level sensor is a direct input to the front control module (that small module on the front of the IPM) where the message is presumably sent to the cluster via the PCI data bus.

To summarize, the bad news is that your new scan tool will not turn off any lights as long as the CAB sees a problem. The good news is that you will probably be able to use your new scan tool to help diagnose why your ABS light is coming on.

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