An ABS sensor sends a wheel speed signal to the ABS control module. If the sensor or sensor signal is not plausible it will normally cause the ABS light to come on and set a trouble code. The brake caliper and caliper guide pins could be a problem, You already replaced them, are they installed correctly? ( A new part can also be defective.) Make sure that the brake hoses to the caliper are routed / installed correctly, and that the mounting brackets are not damaged or pinching the hose shut.
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