The 3 solenoid valves within the modulator assembly control the flow of brake fluid through the system.
Legend and Vigor
If a solenoid leaks excessively, the brake fluid level in the modulator reservoir tank will rise when operating the ABS motor. The modulator reservoir may also overflow.
- Connect an ohmmeter between the terminals of the accumulator pressure switch.
- Attach the positive lead of a fully charged 12 volt battery to the RED/WHT terminal of the power unit motor connector and negative lead to the GRN terminal. Install a switch in the negative lead.
- Turn the switch ON to allow sufficient pressure to build up within the accumulator and check for continuity.
- If the ohmmeter shows continuity (pressure switch turned ON), run the power unit for approximately 10 seconds, then turn the switch OFF .
- Check if the solenoid hisses or squeaks. Replace the modulator if the solenoid hisses or squeaks.
- Check the pressure switch for continuity within 30 minutes. It is normal if there is continuity. if there is no continuity, a solenoid is leaking and the modulator must be replaced.