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> Voltage drop
Dave97
post Sep 22 2020, 05:41 PM
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What is normal voltage drop when you turn on the lights? I’m just going off the volt meter, but I start at about 14.2 driving around, when I pull on even the first notch of the light switch I’ll drop to less than 13. Is it a ground issue? I understand that this a rather common. Thanks. Dave
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davep
post Sep 22 2020, 09:32 PM
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There is a fair current being distributed at the fusebox to run everything up front. As the load goes up, the resistance losses in the wiring cause the voltage to go down. Ever try to read the voltage at the starter when starting? Sometimes the voltage drops to 8. One thing to try is to run separate fused power from the battery to relays for the headlights. This takes a big load off of the old system and provides better voltage to the headlights. Similar is the addition of a relay near the starter to reduce the current through the ignition switch which often burns out; and it is hard to find good ignition switches these days.
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76-914
post Sep 22 2020, 10:33 PM
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QUOTE(davep @ Sep 22 2020, 08:32 PM) *

There is a fair current being distributed at the fusebox to run everything up front. As the load goes up, the resistance losses in the wiring cause the voltage to go down. Ever try to read the voltage at the starter when starting? Sometimes the voltage drops to 8. One thing to try is to run separate fused power from the battery to relays for the headlights. This takes a big load off of the old system and provides better voltage to the headlights. Similar is the addition of a relay near the starter to reduce the current through the ignition switch which often burns out; and it is hard to find good ignition switches these days.

(IMG:style_emoticons/default/agree.gif) Actually it’s very accurate if you run a dedicated wire from the battery to the gauge. Everyone in here has asked the same question when they got their 914. (IMG:style_emoticons/default/beerchug.gif)
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lierofox
post Sep 23 2020, 01:11 PM
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QUOTE(76-914 @ Sep 22 2020, 09:33 PM) *

QUOTE(davep @ Sep 22 2020, 08:32 PM) *

There is a fair current being distributed at the fusebox to run everything up front. As the load goes up, the resistance losses in the wiring cause the voltage to go down. Ever try to read the voltage at the starter when starting? Sometimes the voltage drops to 8. One thing to try is to run separate fused power from the battery to relays for the headlights. This takes a big load off of the old system and provides better voltage to the headlights. Similar is the addition of a relay near the starter to reduce the current through the ignition switch which often burns out; and it is hard to find good ignition switches these days.

(IMG:style_emoticons/default/agree.gif) Actually it’s very accurate if you run a dedicated wire from the battery to the gauge. Everyone in here has asked the same question when they got their 914. (IMG:style_emoticons/default/beerchug.gif)

That's what I did, I used the wire going to the voltmeter as the trigger for a relay coil. Through the relay I ran a wire directly from the battery to the volt meter. Voltage is perfectly accurate now regardless of what loads are on the system.
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