Re: [T3] pump relay problems...

[Jim Adney <jadney@vwtype3.org>]

On 11 Dec 2003 at 16:52, jeff ward wrote:

> I am doing some wire chasing here, the book states that on the fuel
> pump relay itself, if I am not recieving 12v, to  TERMINAL 86, to "
> find the open circuit and eliminate it." Also, I have constant 12v.
> coming into the center terminal, even when the key is out. My question
> is, wha the hell does does " find the open circuit and eliminate it"
> mean, and should I have constant power to that center terminal?? 

The relay takes power from the fuse box and passes it on to the fuel pump when 
the relay is turned on. The 2 wires in the plastic plug turn the relay on; they 
supply the relay coil.

Of the other wires, one comes from the fuse box, and I THINK this wire is hot 
all the time.

A second wire disappear thru the firewall and goes to the pump. This wire 
should be hot only when the relay is on. The relay should be on any time the 
engine is in motion, or within 1 second of just having the key turned on or the 
engine stopping.

70-73 AT cars have a third wire which runs from the relay to the aux air 
regulator. This wire gets power at exactly the same time that the pump gets 
power.

When they say to "find the open circuit" they mean to find the break in the 
circuit that is keeping power from getting to the relay.

Does this answer your question?

-- 
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Jim Adney, jadney@vwtype3.org
Madison, Wisconsin, USA
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