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> NO electrical current to anything, power relay problem?
swb911s
post Sep 1 2022, 04:54 PM
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I have a 74 914 which has been in storage for many years, after installing a new battery I can not get any systems to work when the ignition is turned on... The looms appear to be in very good shape and are unmolested.. Is this a power relay problem? no starter crank action ... nothing seems to work, power seems to be getting to the relay board...Suggestions are welcome.. JON [swb911s]
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emerygt350
post Sep 1 2022, 06:25 PM
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Anything to the fuze box?
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JeffBowlsby
post Sep 1 2022, 06:27 PM
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Check main power fuse and main power relay, both are on the relay board.
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fixer34
post Sep 1 2022, 06:28 PM
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There is no main power relay as such. One big wire from the battery to the starter and one to the relay board which feeds the fuse box directly I believe.
Have you checked the ground straps to the chassis?
Get a voltmeter or even a 12v test probe/light. One end to a clean chassis ground point then start poking at things that should have power. Several fuse positions are 'always on'.
Report back what you find (or don't find..)
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davep
post Sep 1 2022, 07:50 PM
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1974 has the interlock relay under the passenger seat. Unless the seat is sat in and the seatbelt secured, and possibly there is oil pressure, then the logic relay does not pass power to the relay board and thus the starter. The simple bypass is to remove the two big yellow wires and connect them together with a double male spade. Search for interlock here.
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mgphoto
post Sep 1 2022, 10:05 PM
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QUOTE(swb911s @ Sep 1 2022, 03:54 PM) *

I have a 74 914 which has been in storage for many years, after installing a new battery I can not get any systems to work when the ignition is turned on... The looms appear to be in very good shape and are unmolested.. Is this a power relay problem? no starter crank action ... nothing seems to work, power seems to be getting to the relay board...Suggestions are welcome.. JON [swb911s]

First do the dash lights come on, oil pressure, alternator?
If so the starter solenoid could be frozen.
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JeffBowlsby
post Sep 2 2022, 08:06 AM
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Main power fuse and main power relay


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dr914@autoatlanta.com
post Sep 2 2022, 08:09 AM
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check the red wires connected to the battery positive terminal
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swb911s
post Sep 2 2022, 03:00 PM
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QUOTE(swb911s @ Sep 1 2022, 05:54 PM) *

I have a 74 914 which has been in storage for many years, after installing a new battery I can not get any systems to work when the ignition is turned on... The looms appear to be in very good shape and are unmolested.. Is this a power relay problem? no starter crank action ... nothing seems to work, power seems to be getting to the relay board...Suggestions are welcome.. JON [swb911s]



Thanks to all who offered help... and ideas... and support... will follow through and report my findings
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Dave_Darling
post Sep 2 2022, 08:54 PM
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Jeff, that "power relay" is power to the fuel injection. It doesn't really have anything to do with power to the dashboard, for instance.

If you have zero power to anything, no dash lights or anything else, you need to check the battery connections. You've just messed with those, a problem showing up immediately after that points pretty strongly to what you just did.

Check the connections at the battery, that they are clean and tight (and, that you didn't do something like leave the plastic cover on one of the posts--DON'T ASK HOW I KNOW THAT!!). Also look for the red wires that should hook onto the (+) clamp that goes to the battery. And check the other end of both the ground strap (onto the side of the engine bay) and the positive cable (onto the starter).

--DD
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ClayPerrine
post Sep 3 2022, 06:10 AM
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QUOTE(Dave_Darling @ Sep 2 2022, 09:54 PM) *


Check the connections at the battery, that they are clean and tight (and, that you didn't do something like leave the plastic cover on one of the posts--DON'T ASK HOW I KNOW THAT!!).

--DD


Dave--- HOW DO YOU KNOW THAT!?!?!? (IMG:style_emoticons/default/poke.gif)
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Dave_Darling
post Sep 4 2022, 02:21 AM
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Don't ask.

--DD
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ClayPerrine
post Sep 4 2022, 12:58 PM
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QUOTE(Dave_Darling @ Sep 4 2022, 03:21 AM) *

Don't ask.

--DD


(IMG:http://www.914world.com/bbs2/uploads_offsite/external-content.duckduckgo.com-1143-1662317915.1.gif)
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swb911s
post Sep 23 2022, 12:33 PM
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QUOTE(swb911s @ Sep 1 2022, 05:54 PM) *

I have a 74 914 which has been in storage for many years, after installing a new battery I can not get any systems to work when the ignition is turned on... The looms appear to be in very good shape and are unmolested.. Is this a power relay problem? no starter crank action ... nothing seems to work, power seems to be getting to the relay board...Suggestions are welcome.. JON [swb911s]


As promised to the helpful members of this forum... I will follow up on the resolution of this issue... As suggested by persons MUCH smarter than I I concentrated on the POSITIVE battery terminal and found a corroded and broken situation.. after correction the power has been restored along with bringing back to life various motors and systems... THANKS to ALLjava script:emoticon(':beer2:','smid_14')


JON
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worn
post Sep 23 2022, 06:17 PM
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QUOTE(ClayPerrine @ Sep 4 2022, 11:58 AM) *

QUOTE(Dave_Darling @ Sep 4 2022, 03:21 AM) *

Don't ask.

--DD


(IMG:http://www.914world.com/bbs2/uploads_offsite/external-content.duckduckgo.com-1143-1662317915.1.gif)

What a great film. Almost as good as what I see as a scientific documentary set in Transylvania. Pardon me boys…
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