747 VSS Question

[Shannen Durphey]

rr wrote:
> 
> The optical buffers I've seen are lime-green in color. They have
> a three wire cable to the optical head. The edge card conn has
> two sets of outputs, one for the ecm, the other for cruise.
> 
> Recently I grabbed a '747 out of a van that had a small black
> box attached to the ecm mount. At first I thought it was a drac.
> However, no jumpers and not too much inside. Now I'm thinking
> it was maybe a magnetic buffer. Next time I run into one at the
> yard, I'll check more closely for the pickup. An inline mag unit
> that goes to this buffer would be handy.

The DRAC is a magnetic buffer.  The magnetic sensor is part of the
transmission.  The reluctor ring replaces the speedometer cable driving
gear, the sensor sits where the speedo cable driven gear and sleeve
would be.  Theo utside  diameter of the sensor is much larger than most
speedo gear sleeves.
Vans and pickups with Rear Wheel Anti Lock systems usually have an RWAL
controller near the master cylinder.

My memory's failing : (  What color and roughly how many wires were
attached to the small black box you found?
Shannen

> 
> And yes, I've kinda' wondered about that magnet generator
> shown on the prints.
> 
> BobR.
> 
>
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