2. For every turn of the speedo cable 4 pulses are produced by the VSS.
3. The ECU outputs a low voltage (5v) on the VSS pin, this is ground by the VSS which produces the 'pulse'.
4. VTEC will not engage until car travelling at 20 mph, ECU error signal generated if no VSS signal present.
5. JDM Honda's have speed limiters, the VSS signal is used by the ECU to control the limiter.
6. Early CRX 1988-1991 have speedo cable and VSS built into speedo head.
7. Later Honda's have the speedo cable replaced by an electronic speedo's, the VSS is located on the gearbox and control's the speedo and signal to the ECU. My solution to the VSS problem: Having read on the 16v mini forums about someone who had taken the VSS out of the Honda clocks and fitted it to the mini speedo I decided to investigate this option.
I ended up buying a 7mm reed switch from maplins (£1.99) and mounted this into the mini speedo head, the reed switch is mounted next to the magnets within the speedo head that operate the speedo needle.
Initially I thought this would produce 2 pulses per turn of the speedo cable due to the configuration of the magnets but after some testing with the old avo meter I found it actually produces 4 pulses per turn of the speedo cable :-)
