Functional Check Sequence Test
- Turn ignition on. Pump will run and then shut off. Do not allow pump to run more than 20 seconds. Observe that pump stops at 635-735 psi (44.6-51.7 kg/cm2 ) reading on test gauge. Pressure will settle to a slightly lower value after shutoff and then remain steady. Observe for 1 minute.
- Slowly bleed off accumulator pressure with bleed valve, returning fluid to pump reservoir. Observe that pump turns on again at 490-530 psi (34.5-37.3 kg/cm2 ).
- With reservoir cover off, have assistant slowly apply brake pedal and hold at steady medium force. Observe pressure gauge for indication of continuous pressure drop. Pressure drop rate should not cause pump to recycle within 30 seconds of first apply.
- Turn ignition off and remove pressure switch electrical connector. With ohmmeter connected to switch terminals "B" and "C" and ignition off, slowly bleed off accumulator pressure. Terminals "B" and "C" should close at 355-435 psi (25.0-30.6 kg/cm2 ). This is the low pressure warning signal.
- Continue to bleed off accumulator pressure and note sudden drop off in gauge pressure reading at 200-300 psi (14.1-23.2 kg/cm2 ). This sudden drop is at accumulator precharge pressure.
- Assure that pump sump fluid level is at "FULL" mark on inside of reservoir when accumulator is fully depressurized. Turn ignition on and cycle pump several times to remove air by opening and closing bleed valve. Pump "ON" time should now be less than 10 seconds each cycle.
- During pump "ON/OFF" cycles, note sump reservoir fluid level. It will normally be just covering sump hose port when pump is off and 1/2 full when pump comes on.