Before you unplug anything, look at the lights. Every Raven CANbus and ISOBUS node — product controllers, AccuBoom, AutoBoom, SmarTrax, boom sense/speed — carries the same set of LEDs, and they answer most "is it the node or the cable?" questions on the spot. Keep the machine running while you look; anything voltage-related needs a steady 12 volts.
The six lights
- Logic Power — solid when 12 V logic power is present.
- HC Power — solid when 12 V high-current power is present.
- Micro 1 Hz — flashes once per second when the processor is running. If an AccuBoom master-sense system flashes very fast with the master switch on, the console isn't sending the CAN "expect master" message — that's a CAN communication problem, not a node problem.
- CAN Rx / CAN Tx — flash as messages come in and go out.
- Diag 1 — depends on the node. AccuBoom: lit when the master or any section switch is on. AutoBoom: a second ultrasonic sensor detected. SmarTrax/SmartSteer: receiving GPS. Product controller, air cart or planter aux: solid means the calibration is incomplete (a rate, meter or valve cal is missing); flashing means it's receiving meter or encoder pulses.
- Diag 2 — AccuBoom: a wireless remote section controller is in use. SmarTrax: the 3D unlock was accepted. Product controller: spinner/fan/pump RPM pulses, or key presses from a remote section controller.
Two patterns worth memorizing
No Micro 1 Hz on most nodes after a storm = probable lightning damage. No HC or Logic lights at all = blown fuses — and the classic cause is a machine that was jump-started with the CAN system connected. Check fuses before you condemn a node.
Losing nodes, or nodes losing their calibration
- Updated the field computer recently? Update every node too. Mixed software versions drop nodes and cals.
- Voltage dips and spikes from a weak electrical system knock nodes offline intermittently. Check CAN voltages with the machine running and watch for movement.
- A pinched or broken wire that causes a sudden voltage drop will make a node forget its calibration. Test each connection.
Raven CAN or ISOBUS? Look at the spade pins
The 16-pin round connectors look identical. If all four spade pins (1, 7, 10, 15) are populated, it's Raven Gen II CANbus. If only spade pins 1 and 10 are populated, it's ISOBUS.
CAN cable voltage tests
Gen I (4-pin): 1 CAN Power, 2 CAN High, 3 CAN Ground, 4 CAN Low. Pins 1–3: +12 V. Pins 2–3 and 3–4: 2.5 V (±1 V). Pins 2–4: 75 ohms with two terminators, 150 with one.
Gen II (16-pin): 1 HC Ground 1 · 3 Switched Logic Power · 4 Logic Ground · 5 CAN Power · 6 CAN High · 7 HC Ground 2 · 8 CAN Ground · 9 CAN Low · 10 HC Power 1 · 14 Remote Master Signal · 15 HC Power 2. Pins 1–10, 7–15, 3–4 and 5–8 should all read +12 V; 6–8 and 8–9 about 2.5 V (±1); 6–9 should be 75 ohms with two terminators or 150 with one.
The two-terminator rule: a CANbus needs exactly two terminators — one near the display, one at the far end. (Hawkeye and SmarTrax MD run their own sub-buses, so a machine can legitimately have more than two in total.) A single terminator reads 150 ohms across the CAN High/Low pins on its own: 063-0172-369 for Gen I, 063-0173-224 for Gen II.
Node update failed?
The machine has to be running with a good ground, the USB drive can't be huge or ancient, and you must not bump or pull the drive mid-update — that corrupts the files for next time too. Check the program number on the node (P144V111 = program 144, version 111) against the update before loading; the wrong program means a repair trip. Recovery mode for CAN nodes on a Viper 4 is under Administrator Panel > System Manager > Hardware Update; ISO nodes can only be recovered with the Raven Service Tool.
ISO cable pinouts, the IBBC 9-pin test, and the full update procedures for Viper 4, CR7/CR12 and the Service Tool are in the Raven Troubleshooting Guide. We stock Raven terminators, tees, CAN cables and nodes — shop Raven parts or call (509) 838-2209 and read us the lights.
Procedures summarized from Raven's Interactive Troubleshooting Guide and Raven Support Center articles. Confirm voltages against the manual for your hardware. Spray Center Electronics is an independent Raven dealer in Spokane, WA.