TEST OR INSPECTION
Remove rings, wristwatches, neck chains, and any other jewelry before working
around vehicle. Jewelry can catch on equipment and cause serious injury. Jewelry
and tools may short across electrical circuits and cause damage to equipment, or
severe burns or electrical shock to personnel.
Connect air lines at roof turret shutoff valve. Push and release agent discharge button
on roof turret control handle (WP 0004). Check for 22 to 28 VDC between cab roof wire
harness wire 4055 (purple) at roof, bumper, pump cooler junction box control terminal
strip and a known good ground.
If 22 to 28 VDC are not present, go to Step 9.