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Electrical Gremlins
Okay, the engine is in (correctly), pipes are on, and everything is a go for the first firing except for some electrical problems (and an expansion tank on back order). With the battery and every other connection complete we are getting nothing, as in, no lights, no gauges, and the starter does not turn over. Battery is good, and we have power all the way up to the solenoid. The brown wire that comes off of the solenoid and goes to the ammeter is as far as the power is going. I tried all of the posts on the back of the ignition switch and nothing is hot. Any help would be greatly appreciated.
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Hi
Got a GOOD ground?? U should have more than one too.. trace out your big positive all along with a meter referencing to the frame ( grd) you should easily follow your 12VDC potential. At least its traceable to that solenoid. Then it goes from the hot side of the solenoid to most accessories and dash stuff. This is where the alt feed to the battery should be hooked up and other unswitched hots. Make sure you are coming off the right side of the solenoid for pos feeds. Also use good crimped and soldered connections where you can. Followed with some heat shrink. A quick check is pos. lead on the pos. term of the battery then touch the nearest bolthead that's been screwed into the frame. If there's no juice anywhere, I say it sounds like a poor ground or a missing path at the solenoid on in Tim |
yup what he said!
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Ike,
The power path is from the starter solenoid through the circuit breaker nearby. It then goes directly to the ammeter. From the ammeter, power goes back to the top two fuses on the passenger's-side fuse box. There should be a jumper between the top two fuses. I have forgotten this jumper once before (not bad for 600+ harnesses...) so check the voltage at the #2 fuse first. The power then goes back through the F-G junction (large brown and white wires) to the ignition switch. So... Check voltage at each point, in the sequence I've described. It's probably something very simple. :rolleyes: |
Does that mean that the red wire coming off of the ammeter should read around 12 volts with the other end of a multimeter connected to a good ground? I am pretty sure that when we tried this, one probe on the red wire, and the other on a good ground and came up with nothing.
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Ike,
Yes. Both sides of the ammeter should read 12V all the time. If yours doesn't, it is defective. |
Okay, I think that might be our problem. Now we'll see if we can get a gauge replaced that we bought over a year ago.
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One more question. The set of Autometer gagues actually came with a voltmeter, not an ammeter. It, the voltmeter, was installed in the dash by someone at ERA, so I didn't think that it was a problem. Could this be the problem. If so, add it to the list of "Doh's".
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Nope, won't be the volt meter. And I'm skeptical the Amp meter is "bad", thats pretty rare. No question about one thing, voltage should be present on BOTH sides of the Amp meter to "ground". If it's NOT, the I got to suspect your battery is NOT grounded to the "frame" of the car.
Ernie |
Ike,
Yes - this is a Doh! moment... You must connect the two heavy wires that go to the (missing) ammeter together. (#24, I think). If you have a stout stud (say that 10 times fast ;) ) on the voltmeter, connect both wires to it. Be carefull! Short either wire and you may make some serious smoke (although the circuit breaker should present that). |
Ikstaa;
I'm at the same stage as you. While your diagnoising; Recommend you substitue a small battery charger for the battey; makes mistakes and shorts a minor issue in stead of a 600amp short. You can do everything with a 8 amp charger, run lights, turn signals, fan, instruments; even click the solinode gn |
The amp gauge is missing? Well, LOL,,,,,what Bob said! Thats HOW you get the power from point A to point B.
Ernie |
The amp gauge is missing, but in it's place is a voltmeter that came with the kit of autometer gauges. The only problem I can see with the gauge is that the terminals on the back of the gauge are somewhat small compared to the wires that lead into and out of the gauge. This may not be an issue because my dad checked the wires tonight and both the brown and red wires on the gauge are hot. Also, number one and two fuse are hot on the fuse panel. Our next question is, where do the wires on the opposite side of the fuse panel lead to?
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Don't you have an ERA schematic?
If not get one; it well tell you were the wire goes! If you don't understand the significance between amp/volt meter; get some help, before you burn your house/car down. gn |
We have the schematic, but I am at school, and it is at home. I asked my dad if he could see on the schematic where these wires lead to and he made it sound like it did not say where they go.
I understand the difference between an amp and volt meter, I am simply wondering if we should replace the gauge with an ammeter. Also, I am posting these questions to get help. |
Ike,
There is a major difference between what an ammeter and a voltmeter does. In an ammeter, all the car's current passes through the gage. That's why the wires are heavy. A voltmeter only requires a tap to anywhere in the system and a ground. (that's where your second wire should be connected.) By the way - I've changed my mind about the way the large wires are connected at the gage. While the setup would work, it will have the voltmeter "on" all the time, draining the battery if the car is kept dormant for significant periods. The white and brown wires (#27) must be connected together somehow. Or... Alternately, you can run a new 10g wire from the circuit breaker on the firewall (after disconnecting #31 brown) to the 2nd fuse down on the passenger's side fusebox. Tape off the wires at the dash. You'll also have to run a wire from the ACC terminal of the ignition switch to the voltmeter, and a ground to the other voltmeter terminal. |
Okay. I was hoping that the voltmeter measured the current flowing through the wires, and then used a known resistance to calculate the voltage, but I see that this is not the case.
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