I am having what I think to be some electrical problems with the Focus. First off, recently the fuse for the ignition keeps blowing. When I put a new fuse in (a 30 amp fuse located in the box in the engine compartment) and try to turn the car on, the fuse just blows right away. The lights will not turn on either. Any ideas what might be causing this. I've tried tracing wires but I can't find anything wrong.
Also, I am having some trouble with the throttle position sensor. I've told some of you about the problem, but I just can't find anything wrong. I've replaced the sensor and I am still getting a code saying that the throttle position voltage is wrong.
All of this started when I started putting the stock parts back on the car, and I hate the idea that I've screwed something up and can't figure out what.
I know I haven't really given much information, but that's pretty much all I have to go on. I know very little about electrical systems, so I don't really know what else to do. If someone could just give me a few ideas of what else I might look into, I would greatly appreciate it and the sooner the better. My dad is coming to visit at the end of the week and he said that if I don't have it fixed by the time he gets here, he's taking it back to TX with him and he's gonna fix it. Most people would love to hear that, but my parents already do so much for us, and I don't want them to have to do this too.
Hi
Fuses blow for 2 reasons. Either the current draw is greater than the fuse is rated for or there is a short circuit.
I'd look at the areas that you worked on when you were taking the car back to stock. There may have been a cable that cracked and is now shorting against the chasis. Look at the starter leads and work backwards.
When you just turn the ignition to the ON position without trying to start it does anything happen or is that when the fuse blows?
____________________
A man is not old until regrets take the place of dreams...John Barrymore
Yeah, sounds like a short-to-ground. A wire or some connection must be touching bare metal. The fuse blowing is actually a good thing. Atleast its functioning properly, so you have some piece of mind.
Well, when I was putting the car back to stock one of the things I tried to do was replace the positive battery cable, but at the time I couldn't get the starter off. I went out today and got the starter off, but can't figure out how to get the positive cable off of the starter.
I noticed that both of the wires coming from the starter have exposed metal and I'm sure now that is coming SOME of the problem. I tried looking at the wiring diagrams and see if I could figure out something that would relate the two different problems and I don't know if I came up with anything. I'm knew to looking at wiring diagrams, but I guess I'm learning. I just don't know if any of the electrical things causing the blown fuse is also causing the TPS problem. I hope it's all the same thing.
I'm gonna go to Ford tomorrow and see how to get the cable off the starter so that it can be replaced and see if they can tell me the right way to route the cable.
Also, Codger, I don't know if it's blowing when I turn it to on or not. Would that matter at all?
manninej, I would start with those cables that have the exposed wire. Whether they are your problem or not, Id take care of that cause it will eventually become a problem.
There doesnt necessarily have to be a direct short to ground to blow a fuse, though that is the most common problem. The starter itself could be malfunctioning, not working correctly and pulling too much current which Codger mentioned, and as Johnny pointed out, the fuse blowing is a good thing, you know that atleast the built in protection is working.
However, based on what you are stating, I think your problem is most likely in those exposed wiring. I take you found another in addition to the one we spotted when I was there or is it the same cable?
When you get that replaced just put everything back to normal. If that was the problem you will obviously know right away 'cause the fuse wont blow. I dont know yet if it would be tied directly to the TPS issue you are having, but as I mentioned to you at the time, I cant completely rule it out. You can have what is called a high resistance short in which there is a short to ground but is of sufficient resistance to not blow fuses but draws enough power from the system to cause low voltage problems.
Let us know what you find. Definately let us know how to get that cable off the starter cause I am despirately wanting to replace my wires with the 4 ga stuff Ive had laying around forever now.
____________________ My car is a synner! It uses Amsoil Synthetic Lubricants.
2001 Pontiac Grand Prix GTP
It whines a lot, but I like it
manninej wrote: Well, when I was putting the car back to stock one of the things I tried to do was replace the positive battery cable, but at the time I couldn't get the starter off. I went out today and got the starter off, but can't figure out how to get the positive cable off of the starter.
I noticed that both of the wires coming from the starter have exposed metal and I'm sure now that is coming SOME of the problem. I tried looking at the wiring diagrams and see if I could figure out something that would relate the two different problems and I don't know if I came up with anything. I'm knew to looking at wiring diagrams, but I guess I'm learning. I just don't know if any of the electrical things causing the blown fuse is also causing the TPS problem. I hope it's all the same thing.
I'm gonna go to Ford tomorrow and see how to get the cable off the starter so that it can be replaced and see if they can tell me the right way to route the cable.
Also, Codger, I don't know if it's blowing when I turn it to on or not. Would that matter at all?
The reason I asked that is..... If the fuse goes when you just turn the ignition to the on position then there are more possible places that things could be shorting. If it only blows when you try to engage the starter it narrows the probable causes to that particular circuit.
Sometimes the primary issue is just within the circuit that the fuse blows on. There can be secondary causes outside that circuit, for instance, low level shorts etc as SyntheticShield pointed out.
Do the cables that you've found first. If there is still a problem the easiest way to find out where the other issue is, is to pull all the fuses that are not directly related to starting the car. Get the car started and then just put the fuses back in one at a time until the problem comes back. Operate the devices on that circuit for example the rear defrost etc. Make sure that you wait a couple of minutes between each fuse insertion so that if it is a low level problem it has the time to show itself. The last fuse that you put in when things act up is on the circuit that is causing the problem.
____________________
A man is not old until regrets take the place of dreams...John Barrymore
SyntheticShield wrote: Let us know what you find. Definately let us know how to get that cable off the starter cause I am despirately wanting to replace my wires with the 4 ga stuff Ive had laying around forever now.
Well, I got the cable replaced and it's not blowing the fuse anymore, but the MIL is still coming on with the same code. After looking at the wiring diagram and what the Ford service CD says, some of the stuff is starting to make more sense. I'm going to check it out again tomorrow and see if I can trace all the wiring down and see if I can come up with something.
To get the cable off this is what I did:
Disconnect and remove the battery, then remove the airbox and ducting to the throttle body. This will allow you easier access to the bolts that hold the starter on.
The starter is located on the transmission bell housing. If you can't find it, just follow the positive battery cable and it will take you right to it.
The starter is held in place with (3) 13mm bolts. Two are best reached from the top of the car and the other from underneath the car. Pay close attention to how the bolts go into the starter, the two you reach from the top slide through the transmission housing and into the starter, and the one you reach from underneath slides through the starter and into the transmission housing.
Once the starter is disconnected from the transmission, position it so that you can remove the wiring from the solenoid. One of the nuts is 13mm (deep socket) and the other is 10mm. Then follow the cable to the end where it is attached to something (I don't know what) under the alternator. It is also attached with a 10mm nut.
I took the replacement cable and cut it approximatly where the terminal to attach it to the starter was at. I stripped the two ends and connected them using a copper ring terminal.
Reconnect everything and you are ready to go.
Daniel, I don't think I left anything out, but getting it off is going to be the hard part. I'm certain that if I can figure out what to do with it after getting it off, you will easily be able to. A few words of warning though...make sure that you pay close attention to the way the cable is routed and route it the EXACT same way. If not, you are going to have the same problem I did. Also, a good selection of extentions and regular and deep sockets in the sizes I said (I'm assuming it will be the same for you) is a good thing. I also had to use my ratchet wrenches to get one of the starter bolts off, but you might have better luck with a socket. Also, trying to hold the starter in place while putting the bolts back in can be a bit tricky. I didn't have an extra set of hands, but if you could get someone to hold it in place while you start the bolts, it would make your life alot easier.
I'd love to help you do it, cause I'm sure I could do it again in no time, but we are next door neighbors if you know what I mean. Maybe if you plan to head this way again anytime, I could give you a hand.
One more thing, and Daniel you might remember this. My Ford service CD says some possible causes of what is throwing the light.
Two of the possible causes are:
VREF open to TP sensor
VREF short to SIG RTN
Now, one of the wires coming from the TPS to the PCM is labeled V REF and another is labeled RETURN. I'm assuming this is the VREF and the SIG RTN that the CD is talking about, but what does "open" mean and how can it be fixed? I don't want to sound stupid by asking that and I have a vague idea, but I didn't how to word it any other way.
I'll go ahead and put down the other causes, cause right now I'm open to ANY and ALL suggestions:
TP circuit with frayed wires
Corrosion on TP circuit connectors
TP sensor loose pins
I've visually inspected everything, but that doesn't mean that I didn't miss something.
Would starting the car without the TPS in cause this?
manninej, the throttle postion sensor reads throttle position by way of a voltage across a variable resistance, which you may know by know with all the work you have done on it.
Basically there are three pins in the TPS. Two of the pins will be connected in series with a voltage source (your VREF). That is the resistance part of the TPS is 'spliced' in to a voltage source for the lack of a better description. Another way it may be hooked up, and the more likely scenario, is that one pin is connected to a voltage source (VREF) and one pin connected to ground. The third pin, called the wiper is what moves across the resistance part of the TPS. The voltage on the 'wiper' (wiper is an electronic term, it may be called something else in the manual, its what the shaft on the throttle body connects to on the TPS) will vary depending on what position the TPS is at which is controlled by how far you have the accelerator pressed down.
The voltage on your 'wiper' is most likely the SIG RTN or signal return. That is the voltage that is sent back to the ECU to tell it how much demand you are putting on the motor so it can adjust a host of other things.
An 'open' in one of these wires means there is a break in the circuit somewhere. If you were to cut your positive battery cable, that would be an open and you would have no power. So an open in the VREF or SIG RTN tells me that there is a wire cut somewhere or something preventing the voltage or the signal from getting to the TPS or to the ECU. As the manual says like you posted this could be due to loose pins, that is possibly a connector somewhere is not connecting properly or a pin in a connector is bad.
I would normally disregard 'frayed wires' for what you are seeing because of the possibility of there being an 'open' somewhere. Frayed wires arent normally going to create an 'open' condition in a circuit. They can, but not normally. Frayed wires is going to cause the circuit to fry totatlly from making contact with ground or pop a fuse somewhere. But that would be under normal conditions. You had mentioned about the wiring you had when you had the neons on there and unless you are certain that is not the problem I would look into that.
Thats about all I can think of now this late and as tired as I am. As for this problem occuring because you started the car without the TPS, I dont see it happening. The TPS is used in shifting the tranny (ATX) and in fuel control and a few other things. If the problem did occur because the car was started without the TPS then it would have had to have fried something in the ECU. The TPS is pretty much directly connected to the ECU.
What you may want to try and do is trace out thet VREF wire. Im pretty certain it will go back to the ECU. If so then see if you can identify where that VREF is coming from. Is it generated by the ECU or is it coming from the battery in some way. Anyway, something to think about for now.
Let me know how it goes and thanks for the info on the starter cable.
____________________ My car is a synner! It uses Amsoil Synthetic Lubricants.
2001 Pontiac Grand Prix GTP
It whines a lot, but I like it
If I could get my hands on a volt meter or something like then could I just go through and start testing everything and try to narrow it down to a certain area/wire/section or would that even tell me anything because of the way it is connected together?
