Rob’s team diagnosed and fixed seven real Acorn 180 curved stairlift issues for just $175 by video!

Long-Distance Videochat Repair Diary

Executive Summary

Acorn Canada quoted our client over $800 to replace the stairlift batteries with refurbished units—something that turned out to be completely unnecessary. Rob’s team diagnosed and fixed the real issues for just $175, while also uncovering several hidden problems that were causing repeated failures.

Here’s what we found—and fixed:

First, the stairlift’s Vietnam-made AC-to-DC transformer was leaking high-frequency voltage spikes—also called AC ripple—that didn’t show up on the client’s old Fluke 75 multimeter. This ripple was corrupting the motherboard’s operation, triggering erratic behavior, C8 and J5 error codes, and even minor IEEE safety violations due to stray voltages on touchable surfaces.

Second, loose rail fasteners on carpet were causing vibrations that activated an undocumented safety sensor—making the lift stop unexpectedly mid-run.

Third, the upper final-stop strike arm was loose and shifting during operation.
Fourth, the lower final-stop strike arm was misaligned—so it wasn’t engaging properly at all.
Fifth, every rail support post was missing its second holding bolt, creating flex and instability.
Sixth, the upper charging pads were tilted, putting excess pressure on one charging tip and risking long-term damage.

We also replaced the faulty transformer with a clean, lab-grade benchtop power supply—one that will later double as a battery pack balancer, helping avoid future unnecessary part replacements.

And finally, we walked the client through the safe way to remove battery packs—without cracking the motherboard or damaging the spade connectors, a common issue with DIY attempts.

Total cost? Just $175.

Important Safety Note
If you’re ever working near the charging system:
→ Always unplug the AC-to-DC transformer and power down the stairlift completely.
→ This is especially critical if you suspect AC ripple, stray voltages, or a faulty ground.
→ Even a basic AC outlet tester (the $5 kind) can catch dangerous grounding issues—like grounds exceeding the 0.25-ohm NEC/IEEE safety limit.
Your safety comes before any repair.
Rob's Worldwide Stairlift Repairs warned the client about health implications from touching a stairlift with currents nearly everywhere as discovered by the NCV tester.

Client Context
The stairlift—a $15,000 Acorn 180 curved model—belongs to the client’s 85-year-old, mobility-limited father-in-law, who depends on it daily. Frequent breakdowns had become a serious financial and emotional burden.

The client himself is an electronics graduate from 30 years ago and still uses his original grey Fluke 75 multimeter and an old-school omni-mode non-contact voltage ("NCV") tester.

This time, the stairlift kept stopping several feet down the stairs with no error code. He checked both battery packs—each read a healthy 14.4V DC—and after reseating them, the unit briefly woke up and returned to the top dock.

Sensing deeper issues—and knowing Acorn would likely charge for a full reprogramming or battery swap—he reached out to Rob’s Worldwide Stairlift Repairs for a second opinion… and we’re glad he did.