Author Topic: No power at key on??? HELP!  (Read 682 times)

Offline asm74

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No power at key on??? HELP!
« on: August 26, 2007 - 01:41:43 PM »
I've been wiring up my electric fuel pump, using a relay.  At some point my dash lights, wiper motor, etc stopped working at key on (ignition run position).  The starter still turns, and I get power to the dash cluster when the starter is cranking.  But there's nothing otherwise...

Where could I have gone wrong?  I haven't touched the ignition switch or any of the other wiring under the dash however the body and seatbelt harnesses are not connected.

Can the fuel pump relay 12V battery wire go directly to the battery terminal on the starter relay?

I was going to run the fuel pump relay switch (yellow wire) to the acc on the fuse block OR the dark blue from ignition switch... which is correct?  (eventually an oil pressure safety switch will be inserted into the circuit)
73 Challenger




Offline Chryco Psycho

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Re: No power at key on??? HELP!
« Reply #1 on: August 26, 2007 - 09:12:53 PM »
the 12 v feed to the fuel pump relay can go on the starter relay
I would hook the trigger wire for the fuel pump relay to Dark blue
 not sure about the power problem , I assume you still have 12 v feed at the bottom of the column with the key on ? if not it has to be in the ign switch , if you do have power at the bottom of the column it could be in the bulkhead connector but that wouldn`t affect the dash lights etc  :clueless:

Challenger - You`ll wish You Hadn`t

Offline asm74

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Re: No power at key on??? HELP!
« Reply #2 on: August 27, 2007 - 05:49:35 PM »
Thanks for the reply CP.  I'm going to get to it this week sometime.  I really hope the switch isn't broken.   If the key is in, I should hear a buzzing right?  I don't have the door switches installed either, could that cause something fishy?
73 Challenger

Offline Chryco Psycho

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Re: No power at key on??? HELP!
« Reply #3 on: August 28, 2007 - 02:25:13 AM »
the key buzzer is part of the horn relay so it is totally different from the function of the ing switch
dorr switches just ground the interior light circuit so that will have no effect either

Challenger - You`ll wish You Hadn`t

Offline asm74

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Re: No power at key on??? HELP!
« Reply #4 on: September 05, 2007 - 11:09:11 AM »
Well...  I figured out the problem last weekend.   And let me just say that "dumbass" is probably the most appropriate response. But I just want to say that I DID NOT mangle the firewall connector of the forward light harness so that it can fit in the socket backwards.  That was apparently the problem.  Oddly enough when the connector is plugged in upside down, the key-start position will turn the starter motor, but nothing else will work.
73 Challenger