The eprom presumably holds the firmware, so you need both a new component and the code?  And there is only one IC on the PCB so it's presumably a processor with embedded flash.  How do you know it's faulty?  Could you peel off the label saying 220101 so we can see the type number?

Edited By John Haine on 03/08/2018 13:53:10

Edited By John Haine on 03/08/2018 13:53:39

Edited By John Haine on 03/08/2018 13:54:14

I know you have made investigations, however does applying power directly to the latch solenoid unlock the system? if it doesn't there is your fault.

There is no eprom in the system – the chip will be a processor as has been already mentioned. If that is the fault you will need to replace the chip (quite easy) and then find the code it was programmed with (IMHO unlikely to impossible)

I doubt if pcbs were ever made independently of the safes so your choices are down to someone who has a faulty safe with a good pcb (what can go wrong with the rest of the safe except perhaps leaky batteries?) or buying a good safe and hoping you can swap the board. I note your safe seems quite large, but the 'front panel' seems the same as those on cabin/hotel room sized safes that go for £15 upwards on the auction site. 

Edited By Nick Clarke 3 on 03/08/2018 18:09:28

If it's an old PCB, I'd try changing the capacitor before condemning it to the bin.

Electrolytics do tend to expire with age.

Bill

You also have two transistors on there and i would guess one is to switch the solenoid on so check them also , are any of the leds lighting up or changing state when you enter the code ? 

If you have a search on the net for the data sheet for the chip so you can check the pinouts to find the power and ground pin and check to see if it is getting power .

Whats the other side of the board look like ? Have you checked for dodgy solder joints or damaged tracks ? 

The black connector looks deformed , it looks like it is bulging in the middle if it is maybe a crook connection there ?  

If all else fails you could swap that board with an arduino and connect up the keyboard to it , there are plenty of code lock projects on the internet .

Edited By XD 351 on 04/08/2018 00:24:26

Same here and the closest i got to anything that uses any of the numbers was 0405 which is a hex inverter.

I find it hard to believe that the chip just died , usually it is because something else has gone wrong and killed it .

It could just come down to a crook keypad or a bad connection somewhere

The only other option i see is to try and contact the manufacturer and see if a replacemnt board is available other than that it may be a bin job .

How was the combination set? A quick Google shows that there are some witlessly stupid circuits around for combination locks, one for example uses just a dual D type flip flop.

**LINK**

They seem to have limited key lengths and the combination is set by hardware links. So we may be assuming this unit is cleverer than it really is!

.

It appears to be very similar to this one: **LINK**

http://www.hilka.co.uk/support/manuals/s-25ea(ii).pdf

I have the S-25E version of that one, and was hoping to assist Gary … but the pcb is a different layout

… 'though probably functionally similar.

MichaelG.