belts, for mk?,2 a/c alt set-up

[air-cooled or diesel]

my question is I have a mk2 1.6 na, so I have no tach, I have a bosch 90a alt, I have an unaccounted small green wire on loom by alternator, I have put a female connector on it, where does this wire go? I have no tach, so with out this wire my W terminal on alt would be open, this wire could be a ground wire or what does it do, do I keep it hooked up to W terminal? cause I currently have it on the W terminal.

[smokeinmirrors]

 On non-tach MK2s, the W terminal is there to send the signal to the upshift indicator control unit. W can also be used to signal an OEM diesel tachometer if you can find one. Mine is also a green wire, so it sounds like you have it right.

[air-cooled or diesel]

the upshift indicator was done away with a long time ago, I had also unhooked the relay for it too.

[vanbcguy]

The W terminal feeds the dynamic oil pressure warning system too if you have it.  If you have two separate oil pressure switches then you should have the dynamic oil pressure warning system.

[bajacalal]

From my observations, on cars equipped with the dynamic oil pressure warning system, disconnecting the w-terminal defeats the high pressure function of it, but not the low pressure. You will still see the oil pressure warning light when the engine is off with the key ON, until the engine builds the minimum oil pressure.

Since IMO, the dynamic oil pressure thing is hit and miss anyway, and tends to malfunction a lot on our 30 year old cars, disconnecting the w-terminal has no real consequence... unless you want a tach.

[vanbcguy]

On Mk3 cars no W signal causes a flashing oil pressure light. Not sure when that started though.

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