If you have a Clifford Alarm that is a few years old, or perhaps a Clifford alarm that no longer chirps
when you lock/unlock the car (with the setting switched on) READ-ON!
Clifford very cleverly (yeah, right!) designed their alarms so that they use a backup battery so continue to
provide power to the system even when the cables are cut. This is a good idea, but can lead into issues as the
alarms age, because batteries don't last forever!
Within the siren unit itself, Clifford placed a Nicad backup battery. As you probably know, Nicads
suffer from the "memory effect" whereby if left on charge, or not fully cycled properly, no longer hold their
charge. Here's the clever bit: (and you can check your manual for proof) To alert the owner of a failed backup
battery, Clifford decided to set the alarm to NOT CHIRP when you lock/unlock the car when the battery was dead.
Nice warning, huh? Some people wouldn't even notice!
To fix this, we need to replace the backup battery. These batteries contain 6 cells, each cell is 1/2 the length
of a standard AA battery. The total voltage of the battery is 7.2V. A suitable battery pack replacement can be
purchased from ebay for around £13 delivered, or probably from Maplins, or even custom made for less. The standard Nicad is 350mah, replacements of 550mah are a good idea as they will last longer.
Here is a photo of the culprit (new ebay Ni-mh battery on the left, old ni-cad on right):
And here's what you need to do!
1. Unlock the vehicle and place the alarm into Valet mode (the indicator LED will turn on constantly). Disconnect
the main battery from the car by removing the negative lead, obviously making sure you know all of your stereo
2. Locate the Clifford Siren, usually within the engine bay of the vehicle.
3. Remove the siren from the bracket, which can usually be done by loosening both bolts (1 either side of the
siren housing) and pulling the siren down and out. Alternatively, undo 1 bolt completely (catch those bolts and
nuts!!) and the unscrew the bracket from the car.
4. With the siren out of the engine bay, carefully pull as much cable slack as possible to enable you to move
the siren for easier access.
5. Using a posi-driver, remove the two long screws entering the rear of the siren housing. This will enable the
speaker at the front to drop out of the case. Be careful not to drop it and put strain on the cables.
6. On the side of the siren case, you will find the cable entry point. Undo the 4 posi-drive screws from the
bracket, and carefully prise it away from the housing, as it will most likely be glued in place.
7. With the cable bracket removed, the cable should be free to move in and out of the case. Feed some of the
cable slack INTO the housing, and this will enable you to remove the alarm PCB (circuit board) out from the
front, where the speaker used to be.
8. Keep feeding slack through as necessary to get the PCB well clear of the alarm. You should now have something
9. The battery is the big bit sat on top of the PCB. To remove this, cut both cable ties, ensuring that when
the battery is free you retain the plastic sheet that the battery is sitting on.
10. You now have 2 options - 1 is to un-solder the red and black cables from the PCB that connect to the battery
, or you can cut both cables somewhere between the two, and then strip/resolder the new battery to these. I
opted for the latter because the PCB is heavily populated with components near to the solder joints and I didn't
want to damage anything.
11. With the old battery out, it's time to put the new one in! Strip all wire ends (2 on battery and if you
chose the latter in #10 the 2 fly-leads on the PCB) and "tin" them so that they are ready to be joined. Don't
forget the heatshrink material to insulate the joins afterwards.
12. With the new battery soldered on, place the plastic sheet you threw away in step #9 (lol) under the battery
and then onto the PCB as it was before. Use 2 cable ties to resecure the battery to the PCB.
13. Feed the PCB back into the siren housing, ensuring it slots into the PCB guides in the sides. As you slide
it in, pull through the slack in the cable so as not to trap it.
14. When all slack is removed from the case, and PCB held in nicely, reattach the cable bracket using the 4
screws to clamp it in place on the side of the unit.
15. Slot the siren speaker back into the front of the case, and reattach using the 2 long screws.
16. Replace the alarm into the bracket, and tighten the bolts as necessary.
17. Reattach your main battery to the car, and assuming you put it into Valet mode as in step #1, the alarm will
return to valet mode. If you didn't, find your car keys and turn the alarm off!
18. Test your alarm! You should find that the chirps on lock/unlock are now present, and the proximity sensor
chirps work again too!
P.S - any Clifford retailer will try to sell you a new siren at the cost of approx £90 - the above solution
is much cheaper, and only takes around 15mins to do!