Editing Sinclair ZX Spectrum+ Troubleshooting Guide (section)

== Start here: the physical check ==

Sinclair's own Repair Data section opens by noting that '''around half of machines returned as faulty had no real fault''' — the problems were loose or badly fitted parts. Before any measurement:<ref name="sm48" />

# Check the '''heatsink''' first on any reported fault. Is it loose? Are the screws over-tightened?
# Look for dry joints, cracks in the print, cracked boards, badly fitted ICs, and dirty or tarnished contacts, pins, holders and edge connectors.
# Check for damaged keyboard tails.
# Inspect any add-ons and interfaces for broken solder caused by the user wiggling them, and note whether an add-on is itself loose or faulty.
# Look for hairline cracks and breaks in the board, '''especially radiating from the heatsink screws'''.

Knowing what add-ons the machine was used with is a diagnostic clue in itself: the manual specifically says to '''suspect a blown TR4 and/or destroyed RAM if a Kempston interface was used'''.<ref name="sm48" />