W/O Electronic Tester

1. Check that brake lights work and that the brake switch is properly adjusted. The control unit is grounded through the brake lights. If both brake lights are blown, the control unit will not function.
2. Remove underdash panel from left side footwell.
3. Check that air valves at brake and clutch pedals are correctly adjusted and do not leak. The valves should be closed when the pedals are up and open when pedals are depressed.
4. Check that vacuum servo hoses and air valve hoses are correctly connected and not kinked.
5. Ensure vacuum hose connected to intake manifold is not blocked or punctured.
6. Disconnect hose from connection marked ``VACUUM'' on valve housing. Start engine and place thumb on end of hose. Suction should be felt. If no suction is felt, check hose and connection at intake manifold.
7. Reconnect hose, start engine and leave running for about 30 seconds to establish vacuum.
8. Turn engine off and disconnect hose marked ``VACUUM'' from the valve housing. A hissing sound should be heard. If no sound is heard, there is a vacuum leak in the system. Repair as necessary.