Cougar

Nipper is one of the best electrical troubleshooters we have on this site.

Fuse SBF-2 does tie to a number of important areas, mainly for the engine system. If all the fuses in the Main Panel are good then it needs to be determined if power is getting through the ignition switch since it controls power to that area and more.

It does sound like there is a problem with one of the SBF fuses at least. Get a test light and check the power on each side of the fuses in the Main Panel under the hood. Make sure power is getting to both sides of each fuse. If all the fuses are ok in there then checking for power getting through the ignition switch wiring is the next step.

If you want some help with this start a new thread for it and we will be glad to help you. I assume you have already checked the fuses, dimmer control, and illumination control module for the trouble.

The biggest issue at this point is if the battery warning light is turning on.

It should be pretty simple. If the lamp light is on it means the exciter is most likely getting voltage. If pulling the rear connector of the alternator turns the light off that is a good thing and the alternator is bad. If the lamp doesn't turn on then you need to find out why it isn't. There is a break in the circuit somewhere and you need to fix that before you can dertermine the alternator condition.

With all due respect to Fairtax4me these statements are a little confusing, to me at least. Let me go over these to explain some things the way I see them. The alternator has field windings inside it that build the magnetic field inside the alternator to produce the electrical energy needed for the charging. The field windings don't have some sort of protection against low voltage. The windings need to be excited by an external voltage to get the magnetic field started in the windings. This is provided by what is commonly called the 'lamp' lead and is tied to the exciter of the alternator. The external lead ties to the warning light in the dash. Power gets to the other side of the lamp leads from the ignition switch. This is why it is critical that the warning lamp be working so the exciter can do its job and excite the field windings. Once the process gets going then the external exciter power isn't needed. Voltage will build up on the exciter lead as the field builds up and eventually go beyond the battery voltage. This will cause the warning lamp to go out (alternator is working) since it now has about 12 volts on each side of it and very little current will be flowing. If the alternator has a problem the field will collapse and the warning light will turn on again indicating a problem. The field is controlled by a voltage regulator so it makes sure the output voltage stays within a certain range. As the battery voltage goes down the regulator senses that through the battery lead on the back side of the alternator and allows more current to be produced at the output to keep up with the load and keep the battery charged. Anytime the battery voltage goes below 12.5 volts there most likely is a problem with the charging system. It could be due to the alternator, a problem with the wiring external to the alternator, or even a loose fan belt. If a battery has a shorted cell condition that will cause the voltage to go low also and most likely kill the alternator if not caught quickly.

I think you can get that info at a locale library.

You're welcome and good hunting.

I don't have any recommendations for brands but if there are any with a llifetime warranty I would go with that.

One of the fusible links does tie to the alternator output lead. If you measured about the same voltage at the battery and the alternator output then the fusible link is most likely ok. If there was more .2 volt difference then things need to be checked.

The fuse is most likely blowing out when the ignition is turned on. The Main Relay turns on then and supplies power to the O2 sensors and various engine solenoids which most likely is were the trouble is located. If the fuse doesn't blow out until the the ignition is turned ON then the fault is after the Main Relay. To prove that you could pull the Main Relay and see if a new fuse works ok then. Nipper: You should be able to find the trouble with your friends truck in short order I would think.

If the battery warning light turns on when you turn the key from OFF to RUN then most likely the alternator is bad. If that light isn't working though then you need to see why that is. It supplies power to the alternator exciter and the light is in series with the power, along with other warning lights. You also need to make sure that the fused lead between the alternator output and the battery is good. If the voltages are the same at each point then you are good. I guess you did that already though.

Since you have a meter make sure that the alternator is getting at least 13.5 volts to the battery while reving the engine slightly. You could also check for any voltage drop between the alternator output and the positive battery terminal. There should be less than .2 volts with a good load on the system.

It does sound like you are not getting a charge to the battery for some reason. I think there are fusible links used in your car's system so make sure they are making good connection. Also make sure the alternator fan belt is tight and check the wiring connections on the alternator. Make sure they are ok. Also clean the battery connections using a wire brush. It would be a good thing to have a load test done on the charging system to see how well it is working when you get the car running well enough. You may have to put a battery charger on the battery.

Hopefully you didn't damage the power distribution wiring too badly. The trouble may be with the wiring after the Main Relay. It supplies power to the O2 sensors and some engine solenoids along with some other things. The relay should be behind the interior fuse panel just below the the fuel pump relay. The Main Relay is the square one. Remove the relay from the socket and see if the fuse dosen't blow out then. I assume the fuse blew out only when you turned the ignition switch to RUN. If so that means the ECU is ok since power is always running to it, even if the switch is OFF. It is the Main Relay that gets turned on when the ignition is turned on so the trouble is on the Main Relay circuit. It is common for the wiring to the O2 sensors to run across the exhaust pipes which burns the insolation and causes a short on the power lead coming from the Main Relay contacts. This is one possibility at least. The trouble could be with one of the engine solenoids power leads also.

Nipper has a very good point. I didn't realize that the sensors were cable driven so first making sure the flexable cables are ok before blaming the sensor itself makes sense.

After checking the code P1540 it does appear that the sensor may need to be replaced. Some codes refer to circuit problems so the circuit to the sensor needs to be checked rather than replace the sensor. But that isn't the case here.

You're welcome for the help and Merry Christmas to all. Here is a link you can use to download some info from. The bottom one is what you want I believe. http://www.finleyweb.net/JonsStuff/SubaruDocumentation.aspx The trouble very well may be with the door lock timer module since you stated you can hear the solenoids move when power is applied. I would try that module first to see if that helps. The info shows the door timer to be near or behind the passenger kick panel. The security module appears to be behind the instrument panel. Instructions say to remove the panel in order to get at it. The trouble may also be in the cluster so disconnecting it may be a thing to try if other things aren't the problem.

The advice MDJDC gives sounds good to me. Hopefully you can find the box and disconnecting it will eliminate the trouble. In an effort to look into this trouble I checked the wiring diagram and I can't find any reference to a clock circuit. I did find a fuse that is called fuse 25 in the prints and it is located second from the bottom of the row of fuses in the panel under the hood, also called fuse circuit MB-9. I think this is the fuse you are refering to. Here is a list of places the fuse ties to: Door lock timer Headlight alarm relay Interrupt relay Radio Security control module Security indicator light Spot light Room light Step light Combination meter Luggage room light Trailer connector Trunk room light If I was working on this I would start by pulling modules in an effort to find the trouble. Also check the trailer connector. Since you are seeing a pulsing current the trouble is most likely with a module. As an added note this trouble really isn't a short in the true sense but it is a extra current or parasitic current draw.

As far as the bucking problem goes the trouble may be due to lack of fuel pressure. If you haven't replaced the fuel filter I suggest you replace it. If that doesn't help then you way have to replace the fuel pump. If climbing a hill makes the trouble happen then the fuel pump may be getting weak.

If you replaced fuse SBF-2 with a jumper wire at one point it may have caused the trouble on the line to burn out the shorting condition and you dodged a bullet. If that is the case whatever was being supplied voltage past the shorting point most likely won't be working now.

I just though of another thing. I think the power for the turn signals is switched by the emergency flasher switch so try cycling that switch a few times to see if that helps restore things.

If there is no signs of power to the turn indicators then I suggest you check for a bad fuse first off. If the emergency flashers don't work also then I would be pretty sure there is a power problem causing the trouble.

If you inserted a jumper wire in place of the fuse you may now have a more serious problem if the short was still on the line. The arcing from the starter shouldn't cause the fuse to blow. The power to the starter really isn't fused at all, it runs directly to it. I think fuse SBF-2 ties to some engine sensors like the O2 sensor among some other things like the Main Relay. The wiring to it may have touched the exhaust piping and shorted out. I doubt that the ECU is causing the shorting problem. You could disconnect it to prove that. In order to help you find this trouble I suggest you purchase a wiring diagram for the vehicle. You really need it for a guide unless you get lucky and find the short.