Honeywell G2-20 - BAT MISS fault (have replaced battery)

20 Dec 2017
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United Kingdom

I have had a Honeywell G2-20 for nearly 5 years now and have previously replaced the battery a few years ago as I was getting a BAT MISS fault on the alarm.

Recently, I started receiving the BAT MISS fault on the alarm again so I purchased a brand new replacement Yuasa NP7-12 battery from Rexel.

However, the BATT MISS fault still appears and disappears every few hours.

I did test the voltage on the new battery before installing it and it was 12.67V.

The battery is connected correctly.

I did also try to restart the alarm using the engineer options but this hasnt helped.

I have read from previous faults that it may be the PCB that is faulty. Any other ideas?

Also is there a way to get the alarm to ignore the error temporarily so I can exit engineering mode and set the alarm?

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I just checked, the leads do have voltage (reading 13.52V)
Make sure no corrosion on spade connectors and make sure they are nice and tight on battery, and also at terminal end.
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Hi, sorry for the late responses

Bigsosij - I did check the connections and they are tight. I couldn't see any obvious signs of corrosion

Gibbies - Its reading about 13.5V

Still getting the same fault. I have changed the alarm settings so I can set it with the battery fault for now

The only other thing I can think of is to change the battery wires for new ones.

Does anyone know where I can purchase a replacement pair. please. I did try to google it but couldnt find them

This does sound like the PCB has a fault. I think you're wasting your time changing the leads. There's a big SMT 10 Ohm resistor underneath the voltage regulator that can go open circuit and cause a fault in the charge circuit. You need to measure its resistance with all power and battery disconnected and it should be in the low ohms range. This can cause the fault, but there are a few other parts that can cause the issue too.

I do normally keep spare PCB's, but it's been a while since I've sold anything G2 related, as the Flex range is the replacement now.

Thanks for the response. I will take a look at this later on this week. Was really hoping it wouldnt be the PCB :(
Hi, thought I would provide an update in case anyone else experiences the same issue.

I had a separate conversation with GalaxyGuy which helped me out a lot with this issue. Thanks GalaxyGuy

I did notice that the negative connector that connects onto the battery felt slightly looser than the positive connector.

So I used some needle nose pliers on the connector to squeeze down gently on the connector in the hope of improving its connections with the battery.

So far so good..the Batt Miss alert is no longer occurring.

Thank you all for your input into this problem

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