Hawkeye nozzle control valves (NCVs) don't have a screen, but they do talk: each one carries an LED that reports exactly what it's doing. Learn the colors and most Hawkeye calls sort themselves out before the multimeter comes out.
The light code table (Hawkeye and Hawkeye 2)
1 Hz = once per second; 5 Hz = five times per second.
- Green flashing 1 Hz — Ready. (In actuating mode: ready but needs calibration.)
- Blue flashing 1 Hz — Actuating, Auto.
- Blue/Green alternating — Actuating, Manual.
- Red flashing 1 Hz — Loading new software.
- Amber flashing 1 Hz — Alarm active.
- Amber flashing 5 Hz — No ISOBUS communication.
- Green/Magenta alternating — Not calibrated, switch input high.
- Red/Magenta alternating — Not calibrated, switch input has not changed.
- Amber/Red alternating — No ECU detected, or invalid ISO name.
- Amber/Green alternating — Ready, warning alarm active.
- Amber/Blue alternating — Actuating, warning alarm active.
- Solid, any color — NCV failure.
- Dark — No power, or NCV failure.
How indexing works — and why the order matters
Hawkeye always indexes the left side first, center to tip, then the right side. The ECU sends about 8.5 V (±1) to the first left NCV; each valve that indexes passes 3 V on to the next one outward. The right side starts at about 11.5 V (±1). Once indexed, valves are numbered left tip to right tip. So when a boom stops indexing partway, the break is at the first valve that didn't light — count how many indexed on each side and you already know where to look.
Specific nozzles won't index
- Inspect those NCVs and their connections for damage or a loose plug.
- Read the lights against the table above.
- Reset to defaults: Hawkeye menu > Tools > ISO Info > Reset Defaults.
- Swap the suspect NCV with a spare from the service kit or a known-good valve, re-run the calibration wizard, and see whether the problem follows the valve or stays with the drop. A bad valve can be bypassed temporarily with the jumper plug — 115-7303-139 on Hawkeye, 115-2005-070 on Hawkeye 2 — but the system has to be fully re-indexed afterward.
Random nozzles won't index
That's usually software on the ECU or display, or a bad terminator or cable rather than a valve. Verify the counts, read the lights, clear the ISOBUS data (ISOBUS Status > Pool Management > Clear ISOBUS Data, then restart the machine), disconnect the battery for 5–10 minutes and index again, inspect the terminators, re-run the calibration wizard, reset defaults, and update the Hawkeye ECU and display software. You can spray conventionally until it's sorted (see below).
Hawkeye 2: "Multiple Nozzle Offline" with two valves blinking blue
Two adjacent NCV2s blinking blue — one at a 25% duty, one at 75% — with everything beyond them blinking red means the CAN link between those two valves is broken. Do not index, calibrate or update software in this state.
- Run the CAN loopback test to find the pair, and inspect the cable-to-NCV junctions for corrosion or worn contacts.
- With the NCV2s removed, meter the harness: CAN_HI to CAN_LO on the valve, and CAN_HI_OUT to CAN_LO_OUT, should each read 120 ohms ±10%. Harness pin 2 to pin 8 and pin 3 to pin 7 should read about 0 ohms; pins 2 and 3 to pin 4 (HC_GND) and pin 6 (HC_PWR) should be open.
- Any reading out of spec is a cable. The NCV bridge cable — 115-2005-109 for two drops, 115-2005-358 for three — bypasses a damaged link. It's polarized (the "Towards Boom Tip" label faces the tip), never plugs into the faulty drop itself, and only fully repairs a severed trunk on the outermost harness. Re-indexing won't fix a cable.
- All readings in spec: swap a replacement NCV2 into the center-rack side; if it's still blue, put the old one back and try the tip side. Blue clears → index and resume.
Spray conventionally until it's fixed
Hawkeye menu > Tools > Equipment Settings > uncheck Nozzle Control, then open the manual shut-off on the conventional tip at each nozzle body. Only disable Nozzle Control if the bodies are set to bypass the NCVs — the valves stay closed when disabled.
Duty cycle reminder
NCVs pulse at 10 Hz. Never apply below 25% duty (you'll get lateral skips); size the tip so you run around 70%, which leaves turn compensation room in both directions. After changing modes, give it a few minutes for the object pool to load and the DTCs to clear.
Diagnostic cable pinouts, the poppet and seal kit numbers, and flow offset setup for wheel tracks are in the Raven Troubleshooting Guide. We stock NCV poppet kits, jumper plugs and bridge cables — shop Raven parts or call (509) 838-2209 and tell us what color it's blinking.
Procedures summarized from Raven's Interactive Troubleshooting Guide and Raven Support Center articles. Confirm against the manual for your hardware and software version. Spray Center Electronics is an independent Raven dealer in Spokane, WA.