How do you clear the FUS or FU5 message?

(All information here is copyrighted by Brian Keller, 2012).

If this troubleshooting information doesn’t help solve the issue and you’d like to have it repaired, please send it to us.  We repair all models of RainDial timers.

The Irritrol RD-600 series sprinkler controller message ‘FUS’ stands for Fuse.  If you see a 5 (FU5), the 5 represents an S.

This page explains:

  1. What the FUS message really means
  2. How to clear the message
  3. How to determine what is causing the FUS message.
  4. How to fix the FUS message

1. Bottom Line First: This is important to know about the RD600 irrigation timers

  • Despite the RD600 message saying FUS, this does not mean the fuse is bad as one would expect.
  • The FUS message is almost always caused by a shorted solenoid or wiring, not a fuse…).  Solenoids are the cylindrical electrical ‘switch’ that are screwed on the top of the valve; they have two wires going to it. They are fairly easy to replace.
  • In rare cases with the -R series, a full reset resolves the problem.  All the information you need to know is below.

2. To clear the FUS message:

  • Set the dial to the Current Time position
  • Press the + or – button
    • If the FUS error won’t clear, perform steps to do a factory reset
      (try both old and newer timer reset sequences)
  • If the FUS error clears, but keeps coming back, the following information will help figure out what valve is causing the problem and how to fix it:

What valve is causing the FUS message?

  1. If the fuse is good and the message comes back
    1. the suspected “problem valve” number will be displayed on the top of the LCD screen with the FUS message.
    2. Try removing the wire on the terminal board for that valve number, clear the message and run the schedule again.
      1. If you have multiple numbers appearing, remove the wire for each of them, including the MC/Pump wire if you have one.  Clear the message, and run the schedule without the valves connected.
    3. Reconnect the valve wires one by one until you find out which one causes the error to re-appear; this is your suspected bad solenoid.
    4. If you think you have a bad solenoid, you can go to this page for more information: Testing and Replacing Valve Solenoids
    5. If the RD600 series FUS message returns with the same valve number even if you moved the valve to a new location, it’s unlikely that you’d have two solenoids fail at the same time so check the wiring for damage due to recent digging by people or pets, etc…
    6. You can test if the solenoids are bad if you have a meter capable of measuring resistance.  Simply turn off all the valves and measure between the VC/Vcom terminal and the valve/station terminal (e.g., between VC and 1)  every valve including the MC to VC/Vcom should measure around 20 to 40 ohms.   If infinite ohms, you have a broken wire or bad solenoid that results in an open circuit and looks like it’s missing. If you have lower resistance, it’s likely that the solenoid has started to short out and is failing, or your wires are crossed and touching somewhere.  See this post for more information on testing.
    7. If the message appears with no valves or MC/Pump wires connected, try doing a full factory reset (use both the older reset method and newer (-R series) reset methods.  If no luck, it’s still very unlikely to be problem with the controller but if you’re convinced it could be, contact us here.

Other troubleshooting ideas: If the valves are the same, you can swap solenoids with a known working valve and see if the problem follows the suspected bad solenoid.

You can also disconnect the bad solenoid and clear the message.  If you do this, the timer will work normally except for the one valve that was disconnected.

If we’ve helped solve the problem and deserve a little credit, please leave us a donation, we’d really appreciate it. 

For full RD600 series controller reset:
Older models can be reset by removing the battery and power from the controller – this may reset programming. Always try this method first, then the full factory default reset sequence.  All the details can be found in this DIY page:

58 thoughts on “How do you clear the FUS or FU5 message?

  1. Hi
    I only get my FU5 fualt appear in the morning.
    At night I can rub my system full a through test cycle. In the morning I try again but this fault comes up.
    I’ve ran all the systems solo and they work. It’s a weird one, if there was a solenoid failed I would have assumed it would never work.

    • Hi Jesse,

      That’s odd behavior, for sure. I suspect that there is a solenoid that is ‘marginal’ and maybe the temperature variation from morning to other times is making it change just enough to fail. Other ideas/questions below:

      The FUS message should also indicate what valve number is failing. Is it always the same number (see the top row of the display when the FUS msg is visible.) If so, try swapping the valve wires and see if it ‘follows’ a particular solenoid. If it does, replace it.

      Let me know and we’ll troubleshoot it more,

  2. I replaced both of the heads on my irritrol valves. Bought new valves and changed the heads. I initially had a bad solenoid on one of the valves so I just changed both because they were both 15 years old . Instillation problem was FUS and this cleared up after valve change . The problem now is the valve comes on and the controller pulses just as it did before I changed the valves. Does this mean the controller is toast or will resetting it take care of the problem?
    Than you for your help.

    • Hi Rick,

      That’s a symptom that indicates the timer is starting to fail. The good news is that it’s something I repair often, and you won’t have any more trouble with it for many years to come. I’ll send a separate email with details, but you can get most of what you need from the ‘how to get it repaired’ menu.

      Thanks for posting,

Leave a Reply

Your email address will not be published. Required fields are marked *