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Posted by: Ian Stott Jun 8 2009, 07:40 AM

Since I now have a lot of stuff working that didn't work before I guess I am going to come up against new "gremlins". The voltmeter acts like a metronome when the turn signals are on, is this normal for a 914 or do I have a problem some where? The voltmeter drops to around 10 volts when the brakes are applied so I wondering if the brake lights draw that much and is all this related?



Ian Stott
Moncton
Canada

Posted by: SLITS Jun 8 2009, 07:56 AM

If your VOM is in the circuit with the blinkers, it is going to cycle as the power is applied and disconnected ... hence the blink and the VOM is reading voltage to the bulb.

I have seen the same voltage drop on a factory guage when applying the brake lights, but then I am not a Factory Engineer so I don't really know the total draw (blubs, fuses, 35 year old wiring, etc).

Posted by: davesprinkle Jun 8 2009, 10:02 AM

This behavior is normal in a 914, because the voltmeter is measuring the voltage at the fuse-panel, thus detecting the voltage drop along the supply wires.

If you really want to fix the problem, run a separate lead back to the battery. You should switch this lead with a relay so that you don't drain the battery when the car is off. Control the relay with the original voltage sense lead.

Posted by: zonedoubt Jun 8 2009, 10:04 AM

That's normal. The only was to get a "true" measure of the battery voltage is to wire it direct to the battery, using a relay to turn it on with the ignition.

Posted by: zonedoubt Jun 8 2009, 10:08 AM

Yeah, what Dave said.

Posted by: Ian Stott Jun 8 2009, 10:22 AM

Thanks to all who replied, good to know it is normal! I will move on to tackle another issue, running a big power wire from the battery to the front trunk so the stereo guys don't have to go the fuse panel, any pics of what others have done would be helpful and much appreciated.

Ian Stott

Posted by: jt914-6 Jun 8 2009, 12:36 PM

I would suggest something like this. A hot feed comes into the block and you can use any amp of ATO fuse you like for whatever you hook up to it.....

Posted by: Drums66 Jun 8 2009, 12:42 PM

Should keep a nice steady 4/4 time!
or is that 8th note! LOL

Posted by: jt914-6 Jun 8 2009, 12:47 PM

Drums66.......Here's my set......

Posted by: Drums66 Jun 8 2009, 12:52 PM

That's a beauty!!......if we continue with this
topic admin will get uptight!

Posted by: jt914-6 Jun 8 2009, 12:58 PM

Hi-jack over.....

Posted by: Scott Schroeder Jun 8 2009, 01:18 PM

not quite....
This was my main stage rig from 2005-2007 or so...


(sorry - drum addict here...)


Attached image(s)

Posted by: McMark Jun 8 2009, 01:57 PM

I never got into playing a set, but I played the quad toms in high school.

Posted by: Drums66 Jun 8 2009, 04:00 PM

That is a very interesting color?

(sorry - drum addict here...)
[/quote]

OK....I got my fix, back to 914's

Posted by: SLITS Jun 8 2009, 04:05 PM

Personally, I run thu the jungle dressed only in a loin cloth and beat on hollowed out logs.

Posted by: Ian Stott Jun 8 2009, 05:15 PM

I love this hijack! I played drums a long time ago and my most memorable moment was when the Base RSM invited our volunteer band to get off "his" parade square and go "practice" somewhere else. We were humbled but our ego's managed to survive, that was in 1972. If anyone has pics of where they ran the power wire to the front trunk I would appreciate it.

Ian Stott
inept percussionist

Posted by: McMark Jun 8 2009, 07:27 PM

Fuse 11 is a direct run to the battery. Or you can tag along with the stock wiring harness.

Posted by: swl Jun 9 2009, 03:57 PM

Sorry Dave/Zonedoubt but I disagree. Assuming the engine is running the voltage should not drop anywhere near that much. If it is there is a problem that should be looked at - most likely a bad contact somewhere between the battery and and where the vm is tied in. Where ever that contact problem is it will be generating a lot of heat.

Posted by: McMark Jun 9 2009, 04:01 PM

I bet he's not getting a strong 13.8v supply. I bet the voltage drops to 10 because his voltage only reads just above 12 at the highest. The alternator or regulator may be worn out and not putting out full voltage.

But if the drop is from 13.8v to 10v then there is a problem.

Posted by: Spoke Jun 9 2009, 04:31 PM

What needs to be done is get the car in a condition where the voltage drops occur, then with another voltmeter, start at the terminals of the battery, not the clamps, and start measuring voltages. Measure from battery clamp to battery terminal.

Then measure negative battery terminal to chassis, and so forth. The voltage is being dropped somewhere. We can guess all we want about it. It need to be measured to be sure. Could be a ground; could be a terminal connection; could be a dirty fuse or connector.

About the contact problem generating a lot of heat, it would be true if the area causing the high impedance had very little mass. If the offending item was the battery clamp, it is large enough that the heat build-up may be negligible.

Posted by: Ian Stott Jun 9 2009, 05:53 PM

I will do the voltmeter thing this weekend, step by step as suggested by spoke. Upgrading the fuse panel is one of the next items on my need to do list so this will just help in getting all the little gremlins sorted out. Car still runs great and I am sure enjoying it, only time it doesn't get out is if it looks like rain!


Ian Stott
Moncton
Canada