Checking Outlet Valves [HD1]

Checking Outlet Valves





- Ignition off.
- Connect test box and check ground point as per JA. Connecting test box. Connecting Test Box [JA]
- Disconnect control module.
- Jack car up so all wheels are clear of ground. Connect a temporary lead between #1 and #34 on test box.

Connect other temporary leads between #2, #21, #36 and #1 on test box.

- Press brake pedal down hard 3-4 times to remove vacuum in power brake booster overload relay.
- Press brake pedal down hard as if braking suddenly. Brake pedal should feel stiff and pedal should not travel more than 40 mm (1 .57").
- Check that none of the wheels will turn.





NOTE: When ignition is switched on, the outlet valves open. To prevent valves overheating, do not leave ignition on for more than 20 seconds. Wait at least 30 seconds before testing again.





- Ignition on.
- Brake pedal should now go right down when pressed.
- Check that all four wheels turn freely.
- Ignition off.
- Remove temporary leads.

If everything works OK:
- Check inlet valves HD2. Checking Inlet Valves [HD2]

If things do not work properly:
- Try another hydraulic unit as per NE. Hydraulic unit, replacement. Service and Repair