Mercury XL2Z-2C219-BA Control Module

Some variants come equipped with an Anti-lock Brake System (ABS), with early and later models of 2WD possessing a rear wheel ABS, while more modern and 4WD equipped models possess a 4-wheel ABS. The ABS is aimed at improving vehicle lateral control, direct control and reduction of speed through cut-off of breaking system in case of extreme limit of deceleration. The rear anti-lock brake system comprises of the computer module, the anti-lock brake valve, the exciter ring and the sensor as described hereunder; To de-service RABS module, first turn off the negative terminal of the battery, second is to remove the center finish panel, third is to deploy the upper tab of the module and disconnect the electrical connectors, lastly, just install it in the reverse manner. RABS valve requires the detachment of brake lines and electrical connection, unscrewing the appropriate screw and vice versa, placing the valve, screwing the fastening screw and connecting the electrical connection. The speed sensor is at the rear axle housing, and prior to its removal, the area must be cleaned, and a new O-ring seal must be used for the sensor. The good news is that it only transmits through the rear axle, which of course means that the exciter ring needs to be taken apart to be serviced. The 4-wheel ABS hydraulic control unit is positioned in the engine bay and controls the brake fluid pressure to avoid the lock-up of the wheels. Speed inputs for the wheels are obtained through variable-reluctance sensors which in turn produce signals that go to the brake control module that also contains self-diagnostic features. Illumination signs give signals to the driver about a problem and the preliminary inspections a home mechanic can do are inspecting levels of the brake fluid and looking at the electrical connections. If the issues do not disappear, professional diagnosis and repair are advised because of the complexity of the system.