The ammeter on my dash doesn't work properly. With the engine running it usually shows a discharge anywhere from 100-200 amps. The voltmeter is showing 13+ volts so I know the alternator is charging. I've even used my clamp-on ammeter and it is charging.
So I'm assuming the gauge is bad. It's a VDO 0-250 ammeter. Looks like it might be a type b which has an external shunt. No idea where the shunt is located, any ideas?
The gauge has 2 red wires and a brown and orange. I found a VDO document which shows this type but has a + and - wire with 2 sense wires. So not sure if this is the right one or not.
Suggestions?
Forrest you probably have one of the gauge shunt wires broken.. the shunt is most likely in your aft electrical area with big cables attached ... that's what I had found with mine....
Thanks I'll look today for the shunt. Don't think it'll rain today, yesterday was in the 30's and rain all day.
Yes the brown and grey/green wires are for the light.
Here's what I have in the rear electric compartment. 2 heavy red cables with the smaller black wires (why black?) going to 2 small black unmarked blocks with a red wire & black wire on each. The 2 red wires go to the front of the rear electrical panel and are marked as ammeter on a terminal block, then go towards the front. So I assume these are the 2 red wires on the ammeter gauge. With ignition off both red wires at gauge have 12+volts, other 2 wires have 0 volts. With ignition on both red wires have 12volts, orange has 12v, brown has 0 volts.
At the back with ignition on all terminals have 12v.
Yep thats the Shunt. The black wires are going to the individual fuses. The red wires are going to the Ammeter. You should check each fuse for continuity. (remove the wires (look out for sparky!) If the fuses are OK ... try reversing the leads on the meter.. If it goes the other way the meter should be ok.. That would only leave an open in the wire. You said you have power to both sides of the meter.. but if you have one bad fuse the power will feed thru the meter ..
You are measuring FLOW not Power....with the ammeter
Jimmy
(This post was last modified: 02-13-2014, 11:10 AM by Ozarkguy.)
Both fuses are ok. Tried reversing the red wires on the gauge but no change. So it just appears that my meter is reading backwards?
I was hoping to get it fixed but until I can I'll just keep an eye on my voltage.
Thanks Jimmy. And yes I'm quite familiar with Mr. Sparky and his twin brother Smoke!
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