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electrical heebie-jeebies

To: british-cars@autox.team.net
Subject: electrical heebie-jeebies
From: Marcus Tooze <tooze@vinny.cecer.army.mil>
Date: Thu, 11 Aug 1994 09:20:17 -0500
Hi guys,

The '72 Midget was finally ready to crank over last night...however, the
fuel pump wasn't working. I took it out and tested it across the battery,
and nothing. I happened to have a suitable replacement that worked, so I popped 
it in and hooked her up. Now the weirdness set in.

With the ignition ON (red ign. light on) there was no current at the fuel pump
wire. I got out the manual and the diagram showed this (from memory)

                        |---------|
                        |ignition |---|
                        |---------|   |
                                      |
                                      | White lead
                                      |
                                      |
                      |------------|  |
                     8| |---------||7 |
                      | |---------||  |
                      |  fuse box  |  |         Note, the 72 Midget actually has
                      | |---------|| _|         a four fuse box, but the diagram
                     6| |---------||5-          splits it up to make it simpler.
                      |------------|  |
                                      |
                                      |
                                      |
                                      | White lead
                                      |
                                    ______
                                   |fuel  |
                                   |pump  |
                                   |------|----ground

Yes...the unit is grounded...thats not the problem. Yes, the fuse is good...but
that would not effect the fuel pump because it's on the hot side of the fuse 
box. The problem is there is NO current
at the pump OR at the #5 terminal with the ignition switched on. I got under
the dash, and jabbed my tester into white wires there, and they ARE hot with
the ign. on. Now, I only have one wire to my #5 terminal, and I initially
theought there was a wire missing to the #5 terminal. However, the wiring
diagrams are not true to life, and this is a totally un-POed car (well,
untill I got it!), so I figured that fuel pump branch off occurs before the
fuse box i.e:

                        ign.---|----|
                               |    |
                       fuse box|    |fuel pump

So, whats the verdict? I have hot leads coming out of the ignition (tested ok)
yet no juice at the #5 terminal. Probably a break in an unacessable part of the 
harness under the dash??

Is my reasoning on the branch before the fuse box reasonable? Or do I have
a wire missing?

Marcus

P.S. I temporarily bodged a fix, by hooking croc clips from the hot side
of the coil to the #5 terminal....bingo...fuel pump works again when the 
ignition is switched on. By the way, all other white leads are OK with the ign.
on...(e.g, the hot side of the coil).   


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