Kocom intercom repairs and troubleshooting

Every Kocom system, audio or video, is the same three things:

• the outdoor station on the gate pillar or beside the door: call button, speaker and microphone, plus a camera on video models;
• the indoor unit: a handset, or a monitor with a screen, and its power supply;
• the cable between them, often running underground up the driveway.

When something fails, the symptom usually tells you which of the three to suspect. That's how the sections below are organised.

A Kocom that rings by itself is being told someone pressed the button. The usual suspects:

• The call button is stuck or sticky, often after rain or with dust behind it, so it's held down or makes contact on its own.
• Water inside the outdoor station, bridging the button's contacts.
• A damaged cable, where two cores touch, sometimes only when it's wet.

Look at the outdoor station first: does the button spring back, is there moisture behind the front, is the case cracked? If it only happens in wet weather, water is the likely cause. A station that's let water in once will do it again, so it's usually replaced rather than dried.

Visitors press the button and nothing sounds in the house. Work from the inside out:

1. Is the indoor unit powered? Check its adaptor is plugged in and switched on, and that the plug point works.
2. Is the ringer turned down? Some indoor units have a volume or mute setting.
3. Is the gate station damaged? A button that doesn't click, a cracked case or burn marks after a storm.

If the indoor unit is powered and the station looks fine, the cable is next: a break along the driveway after digging, paving or a gardener's spade is a common cause.

On a Kocom video system, sound without a picture narrows it down: the call is getting through, so the power and most of the cable are fine. What's left is the camera in the outdoor station, the core in the cable that carries the picture, or the monitor's screen.

A dark or fogged camera lens is worth a look from outside, and a screen that stays black when you press the monitor's button with nobody at the gate points to the monitor. Beyond that, it needs testing, which is our job. If the picture is there but hard to see at night, the camera may simply be facing into a streetlight or a car's headlights.

You can hear the visitor but they can't hear you, or the other way round. Sound travels one way through the outdoor station's speaker and the other way through its microphone, and the handset has its own pair, so a one-way fault means one of those four, or a core in the cable that carries that direction.

Before calling, try the handset's volume, and listen at the gate while someone speaks from inside: if the station's speaker is silent or crackles, it's the outdoor end. A hum on the line, or crackling that comes and goes with the weather, points to water in the station or a damaged cable joint. The step-by-step checks are in intercom handset no sound.

No ring, no sound, no light: start with the power. The indoor unit's adaptor, the plug point and the distribution board are all quick to check. If they're fine and the unit is still dead, it died after a storm, or other equipment on the same cables failed at the same time, a surge is the likely cause: see gate motor not working after rain or lightning.

If the intercom works but won't open the gate, the fault is in the link from the indoor unit to the gate motor: try the gate with a remote to confirm the motor works. The general intercom checks for any make are on intercom not working.

"Kocom intercom wiring diagram 4 wire" is a common search, usually from someone replacing a unit or connecting a new one. We don't publish Kocom wiring: without the maker's manual for the exact model, a wrong connection can burn out the indoor unit, or send the wrong signal to the gate motor's card.

What we can say in general: the cores in the cable carry power, sound and, on video models, the picture between the outdoor station and the indoor unit, and the indoor unit's gate-release output is wired separately to the gate motor's trigger input. When we replace a Kocom, we check the old cable's cores before deciding whether it can be reused.

Most Kocom faults start at the gate, because the outdoor station is the part exposed to sun, rain, dust and the occasional knock from a car door. A few things help it last:

• Shelter it. A station out of direct rain, under a pillar cap or a hood, lets far less water behind its front.
• Mount it at the right height, at a driver's window, so visitors don't lean on it or press it with a car door.
• Seal the cable entry where the cable comes out of the pillar, so water can't run down the cable into the station.
• Protect the cable route. Mark where the cable runs under the driveway, so building work and gardeners don't cut it.

When we replace a Kocom outdoor station, we check the cable entry and the station's position at the same time, so the new one doesn't fail the same way.

A kocom 1-to-1 audio kit sells for about R880 (Takealot) in a South African shop. Supplied and fitted, published cost guides put an audio system at R2 500–R5 000 (Kandua) and a video system at R5 000–R15 000+ (Kandua). Prices checked October 2026.

Because a Kocom audio kit costs so little in a shop, a repair rarely makes sense for an old audio system with more than one failed part. A cable fault is different: the cable is the expensive part to replace, so finding and fixing a break is worth it. For a video system, replacing just the outdoor station or the monitor is often worthwhile. Compare systems on intercom installation cost.

We repair and install Kocom intercoms across Johannesburg, the East Rand and Centurion, as well as Commax, Centurion, BPT and Zartek systems, and the gate motors they open. Tell us what the intercom is doing (ringing by itself, silent, no picture or dead), and send a photo of the indoor unit and the outdoor station if you can. All our spare parts are genuine, and every repair carries our six-month guarantee on our repairs. Your exact price is set in a free quote before any work starts. No call-out fee when we do the work. If no work is done, a R650 call-out fee applies.

More on our intercom work on intercoms, and the other makes on brands we work on. Repairs Plus is an independent installer and repairer. We are not the manufacturer.