Ford M-series (Visteon)
Instant4000 RDS, 4500 RDS E-O-N, 5000 RDS, Sound 2000, 3000 Traffic, and the earliest 6000 CD units
M123456- Switch the radio on (ignition to position I or II).
- Hold presets 2 and 6 together for 2–3 seconds.
- Watch the display — the serial scrolls past, usually last. Note the letter and 6 digits.
- Nothing? Try the other pair once. Still nothing? It is on the label on the radio casing.