Simplex 4006 - Beeps continuously when LED annunciator is plugged in

Fire Alarm Help
1

Hi,

So as per the title, I recently picked up a Simplex 4006 (specifically a 4006-9121) and I’m having a hell of a wicked problem with it, let me explain as best as I can:

So, this is one of those 4006 systems with the front door LED display, with a cable that runs from connector P7 on the motherboard, to the front annunciator module. (said cable is keyed and has a latch, or at least on mine had a latch, as the latch is broken)

Now, this is where I’m having an issue, when I got the panel, when I tried it earlier today, it worked fine, albeit with some troubles (I have some EOLRs that are missing), everything was fine until I went to close the door to take a picture and when I opened back the door, I saw the cable popped out slightly, then the panel’s screen blanked out, before going back to the “bootloader” message. So as a precaution I shut down the panel, fully unplugged P7, and turned the panel back on with P7 unplugged, got a “Card Failure” trouble, then I turned the panel off again, thinking all was well, plugged P7 back in, and this is where everything went off the rails…

Now, whenever P7 is plugged in, the main board’s beeper/buzzer goes off, non-stop, even when it should not go off (e.g in programming mode, when booting). Worryingly at one point, I pushed on the connector to see if it was properly seated in and managed to get this error code out of the panel:

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To be clear, it hasn’t crashed since, this was purely a one-off. No clue what happened here.

The door annunciator’s buzzer on the other hand, works normally, it shuts off whenever I ack the troubles/alarms, it’s just the main board buzzer that isn’t cooperating.

Please, if anyone can help, or has any idea of what I can try, I’m all ears… I’m honestly at my wits’ end and completely unsure of what to do now. I even tried moving around the jumper near the City Tie card connector, to see if this could change something, unfortunately, it didn’t do anything.

Thanks in advance,
Alexis.

2

Hm, it’s an odd issue. I know someone who’s door-mounted annunciator failed because they unplugged it while powered on. Those things are fragile…

Not sure what went on with yours, but the crash isn’t a good sign. It seems messing with that P7 connector has messed up whatever controls the main board’s piezo. All you can probably do is troubleshoot that circuit, or just rip out that piezo.

The 4006/8 panels are kinda cheap and prone to problems, so this isn’t something too surprising in general.

3

Right… Mine works as it should, or at least it looks to be working, I popped the cover off and can see the Tx/Rx lights blink as they should, so there’s some life in there?

I’ve considered ripping it off but knowing my rotten luck… I’m afraid of making it worse. As for trying to fix whatever controls the piezo, since it only happens when the annunciator is plugged in, this is where it gets confusing, I can somewhat see an optocoupler that connects to P7’s traces, so maybe (and that’s a big, “maybe”) that thing got fried and is wreaking havoc on the board? I’m not even sure where to start.

Otherwise the crash code I got, it was when I bumped the resistor on the S-bus terminals, now I tightened the terminals and now it doesn’t do that anymore (still have the piezo problem, however)

I have never seen another Simplex panel in person, and quite honestly, hearing that kinda makes me wish I had went for something like a 4004 or a 4005.

While I’m at it, do you know anyone who has a spare 4006 board or door annunciator board for sale? I’d hate to buy another 4006 just to pillage it’s board, but if that’s my only other option… I frankly don’t know if the door annunciator is cactus or if it’s really the board.

(sorry for all that rambling, I just can’t help it… Force of habit, yknow..)

4

You can find 4006 boards on ebay, but they aren’t cheap. The door annunciators are harder to find, but they do show up every now and then.
Your experience with the 4006 is probably a sign: less of a hassle getting another Simplex panel. The 4004 is a good alternative, and they aren’t too expensive. The 4005 costs more, but can do a lot of things with the custom control.
If you’re willing to dip into addressable panels, there’s the 4010.

5

As much as I hate to admit it, I think you hit the nail on the head. At least it still works without the LED card (which, looking at it, appears to be a 4606-9111 that had the buttons and keyswitch removed, very curious…) but if one day I can find a suitable replacement board for not too much (or save up for one), I’ll take it and try the LED board with the new main board.

Really it’s a shame that the 4006/4008 are that fragile, I like the form factor of those, plus as I said before, it behaves as it should when I unplug the LED board, so maybe something with the N2 bus got messed up? Hell if I know.

About that, yeah, I was was hesitating between a 4005 and a 4010 (I have some experience with adressable systems) before I stumbled upon the 4006, but if one day I find a 4010 (or hell, a 4005?that isn’t locked out and not too outrageously expensive, I’ll give it a whirl.

I’ll try taking pictures of the board in case there’s something broken or otherwise messed up that I’ve missed on it.

6

Yeah, I have both 4006/8 and they’re fine. However, there’s plenty of examples of them failing or having issues, moreso than their larger/older panels. Out of the few 4006 boards I’ve gotten, one had a dead power supply (no AC power); another had a broken keypad. Both 4008 boards I’ve had don’t detect battery troubles.

You can try diagnosing the issue circuit on the board if you know how. Good chance something backfed power or broke causing the piezo to constantly sound. First time I’ve seen your issue though.

But yeah, I’d recommend giving a 4004/4005/4010 a try if possible. Those are more reliable and more powerful than the 4006 (especially the 4005/4010).

7

Nick, I appreciate the advice, I’ve took another look at the board, aside than a broken battery holder (!) I couldn’t find anything obviously burnt and/or blown, I did see some kind of bus driver chip that seem to tie with P7 and the piezo, I think the smoking gun might be there.

Took some pictures

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Perhaps with a bit of luck, it’s one of those (what I presume is) bus driver chips that has gone bad, not sure about that, I’m still working on tracing out the whole circuit.

Possible, oh, hell, I might even try just rigging up another board harness and connect the LED board to the S-Bus/N2 terminals directly, then see what happens, I just need to trace out the pinout.

Yowza… That’s… Concerning to say the least :grimacing:

8

Best of luck in resolving that issue! Hopefully it’s a small part and not the whole board being compromised.

1 Like
9

Thanks :slight_smile: I’ll keep an eye out for a spare board, just in case I can’t fix this one.

The tricky part will be to figure out which bus driver got blown, and desoldering it (SMD soldering isn’t my forte, at all) and they look to be off the shelf parts, so, I don’t have much to lose trying *shrug*