18-2: Check Isolation Valve No. 1

- Disconnect brake pressure control valve block 16-pin connector.

- Measure resistance between pins 5 and 1.

- Is resistance between 5 and 8 ohms?

YES -- Service circuit 601 (LB/PK). Restore vehicle. Retest system.

NO -- Replace brake pressure control valve block. Restore vehicle. Retest system.