Error started after neighbour's renovation: cable insulation nicked
An E1 error showed up days after the next unit was renovated, and the homeowner feared a damaged control board. The timing pointed elsewhere. Drilling had nicked the communication cable, and the bare wire was touching metal trunking on and off. No parts were replaced.
By Team Snowflake | Reviewed 24 Mar 2026
Case summary
Samsung Wall-mounted5 years oldHDBJurong West, Singapore
- Concern
- The homeowner worried that the renovation next door had damaged the indoor control board, and that a costly board replacement was now unavoidable
- Found
- Communication cable insulation damaged during renovation causing intermittent short
- Key check
- Traced cable route through ceiling void. Found nicked insulation where cable crossed renovation drilling path
- Result
- The E1 error cleared the moment the cable was repaired, and the unit has run without interruption since. No parts were replaced, so the homeowner avoided the board cost they had feared.
What we were told
The aircon began showing an error a few days after the next unit was renovated. Nobody had touched the unit, yet the error turned up around the same time. It came and went, running fine for hours before the error returned.
What we checked
The timing did most of the talking. An error that appeared right after nearby renovation pointed to physical damage to the wiring, not a part wearing out on its own. So we traced the cable route first, before testing any components.
The E1 error was intermittent. The unit ran normally for stretches, then faulted, which rarely happens with a truly dead board.
Both the indoor and outdoor control boards had power and responded to reset commands, so neither board was failed.
The communication cable showed good continuity when the unit sat still. That ruled out a clean break and pointed to a fault that depends on movement.
Tracing the cable through the ceiling void revealed a nick in the insulation, right where the cable crossed the drilling path from next door.
The bare copper at the nick was resting against the metal trunking. Whether the two touched depended on where the cable sat, which explained the on-and-off fault.
What we found
Drilling during the neighbour's renovation nicked the communication cable in the shared ceiling void. The exposed copper then sat against a run of metal trunking. When vibration or heat shifted the cable, the bare section touched the trunking and caused a brief short. That short scrambled the signal between the indoor and outdoor units, which is what the E1 code reports.
What fixed it
We sealed the nicked insulation with heat-shrink tubing, then used cable ties to hold the cable clear of the trunking so the two could not touch again. No parts were replaced. The control boards, the wiring, and the rest of the unit were all undamaged. We also advised the homeowner to photograph the damage, in case they wanted to claim against the renovation contractor.
Outcome
The E1 error cleared the moment the cable was repaired, and the unit has run without interruption since. No parts were replaced, so the homeowner avoided the board cost they had feared.
What this case teaches us
An error that started after nearby work usually traces to the wiring
- An E1 communication error means the indoor and outdoor units cannot talk. The board itself is often fine; the link between them is the first thing to check.
- An error that comes and goes points to a loose or shifting connection, not a dead part. A failed board would fault steadily, not for hours at a time.
- Note when the trouble began and what changed nearby. Drilling, renovation, or any work in a shared ceiling void can nick a cable and cause faults that look far worse.
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