Brake System Warning Indicator Test
- If brake system warning indicator stays off, check for blown fuse. If brake indicator remains on with ignition switch in "RUN" position and parking brake off, a leak in one of the brake systems is indicated.
- Verify leakage by removing connector from brake pressure switch. If indicator goes out, brake pressure switch was closed (low pressure in one system). Repair as necessary. If indicator remains on, check for short in parking brake switch, ignition switch or wiring.
- If brake indicator comes on when ignition switch is in "START" position, but not when parking brake is on. Measure voltage at Tan/White parking brake switch wire with ignition switch in "RUN" position and parking brake applied.
- If battery voltage is at Tan/White wire, install a new parking brake switch. If zero voltage is at Tan/White wire, check wire for open between switch and bulkhead connector (front of dash, left side).
- If brake indicator comes on with parking brake on, but not when ignition switch is in "START" position, check for voltage at ignition switch "START" terminal. If battery voltage is found, install new ignition switch.
- If no voltage is found, check Tan/White wire for open between ignition switch and bulkhead connector. If brake indicator does not come on with low brake accumulator pressure, check for battery voltage at brake accumulator pressure switch terminal (Tan/White wire). If voltage is found, install new switch.