Hot answers tagged

22

The maximum rating of 25A will be for continuous use. The 40A fuse is there to blow very quickly in a fault condition. If you look at this page https://en.wikipedia.org/wiki/American_wire_gauge 2mm² wire will take 166A for 10 seconds or 633A for 1 second before it will fuse. So the 40A fuse will have blown long before the 2mm wire will fail.


21

While the twist/tape method will make the connections and work, I tend to leave this for the quick fix. Over time, with the everyday vibrations occurring, this method tends to allow for continuity issues and things stop functioning. Another easy type fix is wire nuts. This takes very little time, is more secure than the twist/tape method, and doesn't ...


20

Corrosion on the terminals is due to hydrogen gas being released from the acid in the battery. It mixes with other things in the atmosphere under the hood and produces the corrosion you see on the terminals. Generally, if the corrosion is occurring on the negative terminal, your system is probably undercharging. If on the positive side, it is probably ...


19

Heat and thermal stress, even at engine bay temperatures, is not generally the cause of copper wire failure. There is "hydrogen embrittlement" for copper but that only really comes into play at 400C+ in hydrogen-rich environments, usually during annealing. Also, the 20-30C higher range from your hotter climate is pretty negligible from copper's point of view....


16

No, you don't have to rely on wire colors to figure out what's what. With nothing more than a decent multimeter and premix flame (blowtorch or gas stove), a two-test sequence can reveal the identity of each wire, assuming the O2 sensor is fully-functional: Determine the heater wires This should be done first. These wires serve to heat up the O2 sensor to ...


15

This engine is equipped with a voltage regulator. Depending on the exact construction of the regulator a reverse current would be disastrous, especially the high current from a starter battery


15

@Pᴀᴜʟsᴛᴇʀ2's answer is excellent. But, I'd like to add: rather than just twist & tape, there's something called a "lineman's splice," or "Western Union splice" which provides a great electrical connection as well mechanical strength, and is easy to do. (see Wikipedia's illustrations., or google "lineman splice" or "Western Union" splice - there are a few ...


13

The frame ground is needed. Although the engine is bolted to the frame all the connection points are isolated hence insulated by rubber. The reason for the rubber mounts is to isolate the engine vibration and the resulting stress from the frame. Some older vehicles did use a single ground to the block. This required a second ground wire from the block to the ...


12

How can I convert the DC current from my battery to power the blender in the Jeep? The only solution is a 12V DC to 110V AC inverter. Google is full of this, so I just linked google. Your blender has nearly 400W, so you should look for something in the 500W range to have some margin. However, this makes 400W/12V=33.3A, which is very unlikely to be ...


11

absolutely DO NOT replace a BALLAST with a RELAY. They perform different functions completely and are in no way related. Relay = Switch Ballast = Current Regulation A solid state relay may have some voltage limitation attributes but you need to be sure that it matches the ballast that will be provided with your HID kit. I HIGHLY recommend you use those. ...


10

When you say "embrittlement", are you talking about this? This is a common issue with PVC used as insulation: PVC is brittle by nature an needs plasticizers to be added to it when making cable insulation. Over time, plasticizers evaporate (remember that "new car smell" which gradually goes away?), brittling the PVC. Is there anything that one can do to ...


10

Why not just put a wrench on the crankshaft? Ignoring the electrical repercussions, I fear damage to the starter, too. Besides, if the starter on this tractor uses a sprag clutch (and probably most other designs), it wont engage backwards, anyway.


9

This is quite easy, but you need to do yourself a favor and get a factory wiring diagram. It will save you hours of frustration and confusion. The factory wiring diagrams will tell you exactly when the circuits are active and when they aren't. On top of that they will tell you the colors and sometimes the current flow. You really don't want to hook up a ...


9

The connector will need to be replaced. It looks to be fused together. The metal connector terminals were the cause of the original problem. The usual problem is that the connector makes poor contact due to loose fit in the female terminals this causes resistance and therefore heating of the connectors.


8

I can think of several reasons straight away: Cheap Easy to replace Have a very distinctive click that makes it obvious when they are on, and when a bulb has failed Are very well understood Anyone can fit one without needing to understand much about electronics


8

Looks like the starter drive is the typical spring loaded drive gear that engages when the starter motor turns in the "forward" direction, then disengages if the engine starts running and overdrives the starter gear forcing it to disengage. So if you run the starter motor backwards, the starter gear won't engage at all, and the starter will just spin. And ...


7

When you buy a replacement battery cable they come with additional wires with crimp connectors on them for applications that require it. That way the aftermarket supplier can make one part number fit several vehicles. Take the picture below it fits vehicles that have a side post battery and need a 45 inch length. The extra wire may or may not be required ...


7

You should maintain both ground wires. If you removed battery to chassis you would have to add engine to chassis wiring. The battery to engine wire is there to ground the alternator. Battery to chassis wiring is probably a safer, shorter, and easier run than engine to chassis anyways so why bother. You probably want 2gauge wire all the way around. You ...


7

What you need is a simple switch. Here's an example of one that you can order from DigiKey. Your radio will use two wires for powering itself, the ground (GND) and V+. The ground wire should be grounded, that is connected to negative (-) terminal of the battery. The V+ wire should be connected to one connector of the switch. Battery positive terminal (+) ...


7

I took my car to a different VW shop (not the dealership) and they fixed the problem for $160, but if I'd known the solution was just to solder the wires directly together, I could have fixed it myself. I did however, learn what the problem was thanks to them and I'll share the solution here. VW apparently knows about this issue and supposedly offers special ...


7

If there is nothing connected to it (which can draw power), no power will be drawn. To me that means there are no drawbacks. I would not have an issue of making the socket as always hot for just the purpose you suggest. NOTE: I don't know what else I can add here.


7

The very short answer is that heat isn't a significant problem for the wire. Heat is a problem for the insulation. So if you have wires failing I think there is something else going on. The problem with dealing with failing insulation is that there isn't much you can do about it – short of rewiring the affected parts. In a modern car that could be a non-...


7

0.85 mm² copper wires have a resistance of about 0.02 ohm/m, and when a current of about 10 A is driven through this wire, it dissipates about 2 W/m. This isn't soo much and should not be a problem. But there are other weak points: Junctions and switches might not be designed for this current. And the bulb itself becomes really hot, since it ...


6

If you place a jumper wire between a always-on 12V source and a switched 12V source, you've now turned your switched wire into an always-on wire (with power supplied from your original always-on source). This is not advisable, and is almost certainly not what you want. It could also create a risk of fire if the fuse for your unswitched source is too large ...


6

Dont you have to remove the connector with the green/black wire also? In your photo it looks like the connectors are melted together. You can get a knife and try to seperate them first. The blue wires goes to your blower speed setting switch on dash. The green/black wire goes to the blower. Even if you remove the connector. The old connector may not fit to ...


6

TL;DR: You're on the edge, instead of pushing it, use the existing circuit to control a set of relays and supply the bulbs with a short run of larger wire. Use at least 3.3 mm² (12 AWG) wire, which you can fuse at 20 A. Use wire rated for "under hood" (high temperature) applications such as type GXL or TXL. You didn't ask, but I think it worth noting that ...


5

Much of the corrosion is due to bimetal contact between copper and lead alloys. Nothing to do with Hydrogen.


5

I'm going to answer this in a general way because for someone to tell you what the wires mean, they would need to follow this procedure, or have access to detailed wiring diagrams for your car. You'll need a multimeter for this, and you'll have to take apart the brake light as if you were changing the bulbs so you have access to the bulb sockets. I'm ...


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