Electronic Lock Coil and Latch Replacement: When and Which Part

Short answer: if your electronic rim lock gets 12 V from its supply but no longer releases, the coil has usually failed, and a replacement coil such as the LKCL-10 costs ₹599. If the lock releases but the gate will not stay latched, the latch holder (strike) is the likely culprit; the LH-RMLK latch holder costs ₹450. If the lock body, cylinder or mechanism is damaged, replace the whole lock: a lock only costs ₹2,450 to ₹3,799, and a complete remote kit starts at ₹3,049.

Most "dead" gate locks only need one small part. This guide helps you find which one, explains why coils burn out, and lists the spare parts on our store with live prices that include GST.

What does the coil do in an electronic lock?

Inside an electronic rim lock is an electric coil. When the supply sends it a short pulse of 12 V, the coil pulls a part of the mechanism that frees the latch, and the gate can be pushed open. When the pulse stops, the latch is free to catch the strike again when the gate closes.

The coil is designed for short pulses. The LKCL-10 coil listing says a lock coil can get damaged by continuous current, so you should avoid giving current for a long time. The RML-8K lock listing also names a burnt coil from wrong wiring or continuous power as not covered by warranty.

How do I know if the coil has failed?

Work through these checks in order. The first two rule out the supply and remote, which fail more often than people expect.

1. Check the supply and trigger. Press the remote, switch or app. Does the supply's relay click or its light change? If nothing happens, the problem is the remote, receiver or supply, not the coil. Our 10 checks for a lock that will not open covers this.
2. Check the voltage at the lock. Ask an electrician to measure the voltage across the lock wires while someone presses the remote. It should be about 12 V for a moment.
3. Listen at the lock. If 12 V arrives but the lock makes no sound and does not release, the coil is the most likely fault. The LKCL-10 listing puts it simply: if the lock is not operating by 12 V, change the lock coil.
4. Try the key. If the key opens it smoothly, the mechanism is fine and only the electric side has failed. If the key is also stiff, the latch or cylinder needs attention.

Why do lock coils burn out?

• Continuous power. A supply or relay that stays on instead of pulsing. In Wi-Fi kits, the listings tell you to keep the Smart Life inching timer at 1 second for this reason.
• Long unlock time on a door phone. The Combo-CN133 listing notes the lock should not be powered continuously for more than 7 seconds when unlocking.
• Someone holding the button. A push button wired straight to the lock, held down for a long time, can overheat the coil.
• Wrong wiring. Connecting the lock to the wrong terminals of a supply.

Fix the cause before fitting a new coil, or the new one may fail the same way.

How to replace an electronic lock coil

General steps. If you are not comfortable opening the lock, have an electrician or locksmith do it, and follow the manual for your lock model.

1. Switch off the supply at the mains.
2. Take the lock off the gate or remove its inside cover, keeping the screws safe.
3. Photograph the wiring so the new coil goes back the same way.
4. Remove the old coil and fit the replacement in the same position.
5. Refit the cover and lock, then switch on.
6. Test with a short pulse from the remote or switch, and check that the latch catches again when the gate closes.
7. Check the pulse length on your supply, app or door phone so it stays short.

The LKCL-10 listing says the same coil fits CP Plus, Alba, Secureye, Hikvision, Realtime and OEM electronic rim locks. The listing also states there is no warranty on lock coils, so getting the cause right matters.

When is it the latch or strike, not the coil?

If the lock releases normally but the gate swings open, will not stay shut, or needs a slam to lock, look at the latch and the latch holder on the frame:

• The gate has sagged. Heavy metal gates drop slightly over time, so the latch no longer lines up with its hole. Realign the latch holder or adjust the gate hinges.
• The latch holder is worn or bent. Replace it. The LH-RMLK is a latch holder, latch stopper and latch hole for electronic rim locks; its listing notes it is an accessory, not a lock.
• The cylinder is stiff. The Combo-CN133 listing suggests a powdery lubricant such as pencil powder for the cylinder.

Spare parts and replacement locks (27 October 2026)

Part	What it is for	Price
LH-RMLK latch holder	Latch holder, stopper and latch hole for electronic rim locks	₹450
LKCL-10 lock coil	Coil for electronic rim locks: CP Plus, Alba, Secureye, Hikvision, Realtime and OEM. No warranty on coils	₹599
Outside RFID reader	125 kHz EM card reader for RFID motorised locks, weatherproof design. Lock not included	₹599
PCB for motorised lock	Replacement control board for a motorised lock	₹949
FPHL-900 tubular latch	60/70 mm adjustable tubular latch for the FPHL-900 handle lock and lever handles, doors 35 to 45 mm	₹999
ADEL 788 latch	Latch for the ADEL 788 biometric door lock	₹1,499
Secureye SC-S-200EL	Replacement electronic rim lock, lock only	₹2,450
Combo-CN59	New RML-8K lock with receiver, 12 V adapter and 3 remotes	₹3,049
RML-8K lock only	Weatherproof 12 V DC rim lock, 32 mm brass cylinder, 8 keys	₹3,799

Repair or replace: which makes sense?

• Coil failed, lock body fine: replace the coil (₹599) and fix the cause.
• Gate will not stay latched: realign or replace the latch holder (₹450).
• Motorised lock dead, but key and motor sound fine: ask us whether the PCB (₹949) suits your model before buying.
• Lock rusted, cracked, or water-damaged: replace the lock. Note that Combo-CN59 (₹3,049) includes a new RML-8K lock plus receiver, adapter and 3 remotes, and costs less than the RML-8K lock alone (₹3,799), so if your supply is also old, the kit is better value.
• Remote or supply faulty, lock fine: see Wi-Fi lock supplies or the 433 MHz remote and receiver guide.

Browse lock accessories and spare parts and electronic rim locks. For the RML-8K and its kits, read the RML-8K guide. Not sure which part you need? Send a photo of the lock and its label on WhatsApp. Delivery across India is free and orders are prepaid.

FAQ

How do I know if my electronic lock coil is burnt?

If the supply clicks and about 12 V reaches the lock when you press the remote, but the lock does not release, the coil has most likely failed. The key still opens the lock by hand.

Which brands does the LKCL-10 coil fit?

Its listing says it fits CP Plus, Alba, Secureye, Hikvision, Realtime and OEM electronic rim locks.

Is there a warranty on a replacement lock coil?

No. The LKCL-10 listing states there is no warranty on lock coils, because continuous current can damage them.

Why does my electronic lock coil keep burning out?

Usually because it gets power for too long: a relay set to stay on, a long door phone unlock time, or a button held down. Keep the pulse short, such as the 1-second inching the Wi-Fi kit listings recommend.

My gate opens but does not lock again. Is it the coil?

Usually not. Check whether the latch lines up with the latch holder on the frame; a sagging gate or worn holder is the common cause. The LH-RMLK latch holder costs ₹450.

Prices are NavKar Systems website prices on 27 October 2026, inclusive of GST, and may change.