J2 Check ABS Valve Operation

- Turn rear suspension leveler compressor switch OFF if so equipped.

- Turn ignition switch to the OFF position.

Anti-Lock Control Module:

- Disconnect anti-lock brake wiring plug from anti-lock brake control module.

Breakout Box:

- Connect Rotunda EEC-IV Breakout Box 014-00322 with Anti-Lock Test Adapter T90P-50-ALA or equivalent to the anti-lock 55-pin connector on anti-lock brake wiring harness.

- Lift vehicle and rotate wheels to ensure they turn freely.

- Jump pins 19 and 34 at breakout box.

- Short pins 20, 2 and 60 to each other at breakout box.

- Apply moderate brake pedal effort and check that LH front wheel will not turn.

- Check to see that LH front wheel turns freely when ignition switch is in the RUN position.

- Turn rear suspension leveler compressor switch ON when vehicle is off hoist, if so equipped.

CAUTION: Do not leave ignition switch in the RUN position for more than one minute, or valve damage may result.

- Does wheel turn freely?

YES -- Turn ignition switch to the OFF position. Disconnect wire leads. Go to J3. J3 Check ABS Operation RH Front Wheel

NO -- Verify correct wiring between 55-pin connector and 19-pin connector on brake pressure control valve block. If anti-lock brake wiring is correct, replace brake pressure control valve block.