Cougar

I suggest you check the voltage getting to the radio using a meter or a test light probe at least. It sounds like there is a internal problem with the radio.

I suggest you at least put the motor back in place and hook up the resistor pack so the wiring is making a complete connection. Turn the blower on to the HIGH setting and see if the blower works there. If not then check to see if voltage is getting to the motor. If there is no voltage there then the blower relay is most likely at fault or there is a bad connection to the relay socket. I think the relay is located in the upper left side of the dash. If voltage is getting to the motor then the thermo protector in the resistor pack is most likely open.

I think the relays located in the fuse panel under the hood are for the AC and headlights. The Main relay and fuel pump relay are located above the interior fuse panel if I remember correctly. I'm not real sure though.

The battery connections are always the first place to start when looking for this kind of trouble. Another place to check when this kind of thing happens is the fusible links. They can have a bad connection at times also. They are in the plastic box mounted on the coolant reservoir.

I suspect that the service folks may go with a rebuilt unit rather than a new one in order to save on costs.

It is hard to say what caused the current drain trouble. It sounds like the drain has gone away, for the moment at least. Keep an eye on things. If there is a connector getting hot then there is a bad connection there and you may need to replace the connectors going to the heated area. You can run a seperate byass connection if needed.

Try tapping on the relay to see if that gets the blower going. If it does then you know for sure the problem is with the relay.

Check the dimmer control circuit. I assume you have already made sure the control is set to the max position.

I seem to remember you saying you had the factory wiring diagrams and if so you can look to see what the green fusible link ties to and check those circuits. If pulling all the fuses tied to that link still doesn't clear the drain then something has most likely been added to that branch of the circuit. Something before the fuses and after the green link.

There may have been a voltage spike that caused the diodes to fail. It is hard to say if the failures were related or not. You can check the diode as long as there is no other path for the test current to flow. That is why isolating one end of the connection is a good idea.

If you suspect the lights are causing the drain then simply disconnect the power to them and check your current again. If the current drops down to a normal level or zero then you have found the other drain problem.

Thanks for the vote of confidence guys. I'm glad to help you out of your electrical woes. Edrach is a good man also for things like this. Grossgary stated in the original post that the current drain dropped when the fusible link to the fuse panel was pulled. One of the fuses in there should tie to the sense lead of the alternator so that part of the problem has been found. If there still is a current drain with the alternator and the lead to the fuse panel disconnected then it would seem to me that something extra has been added to the power buss somewhere. If there is still a problem with the fuse panel connected then there should be a fuse inside it that will tie to the trouble circuit.

The main output wire of the alternator ties to the battery through the main fusible link. Remove that lead also and see what your current drain is then. Since the lead is hot remove the battery ground lead first before you work on it and keep the lead isolated from touching anything. You have already proved the alternator has a problem with the sense lead so the alternator needs to be replaced. Maybe the rest of the excess current draw is going through the main lead. Blocking diodes inside the alternator can fail and cause this kind trouble. Normal current draw should be less than 30 milliamps and maybe around 15-20 as an average.

Thanks for the update.

The wire may go to the fuel pump relay or it may go to the ignition circuit, I'm not sure which one.

Actually, if the AC ripple voltage is more than 0.1 volts AC there is a problem. One volt of AC is way too much for the battery to handle.

Like Grossgary stated, clean the battery terminals. While the alternator may be putting out a good output it will be diminished if the battery connections are dirty. This is most likely the trouble. If that doesn't help then have the battery tested to check its' capacity. Also try cleaning the battery to chassis ground.

I also suspect the relay is at fault. You could most likely tap on it and make the blower turn on if the relay is at fault.

I suspect there is a grounding problem causing the trouble. You could try running a temporary ground jumper from the battery to a good ground spot under the dash to see if that clears the trouble. If that doesn't work then try the rear lighting area.

Do you at least have a test light probe to verify power with? If not you need to get one, or a voltmeter. Using one of those tools I would first verify that power is getting to both sides of the fusible links. Then move on to the fuses that blew out and make sure power is getting to them.

The tachometer should tie to the minus side of the ignition coil on a yellow wire. Check that connection. For the fuel gauge problem check to see if there is any voltage getting to the black/yellow wire at the sensor with the ignition switch ON. If not, then there is a bad connection to the gauge.

After going over the previous posts here it looks to me you guys are on the right track. The only thing I noticed that should be done is a fuse needs to be placed in the main alternator output lead that ties to the battery in case the main lead gets shorted at the alternator somehow. The fuse may need to be around 80 amps or slightly more than the rated output of the alternator. The 'S' lead of the alternator is the battery sense lead which needs to tie to the battery through a fairly small fuse. It normally uses the b/w wire like you stated. It senses the battery voltage so the internal regulator will know how much current to produce to keep the battery charged up. The 'L' lead is the lamp lead that normally ties to the w/r wire which is connected in series with the battery warning light and then to switched ignition power (the ignition switch). The lead supplies power to the exciter field of the alternator which gets the alternator action started.

The low voltage reading you saw does mean that there is break in the wire connection to power. You should see about the same voltage that the battery is at when things are good. Sometimes connection pins get dirty and can cause that kind of thing to happen. By pulling the connector apart and reconnnecting it usually fixes that. I assume you have verified that all the fuses are ok before digging deeper into the trouble.

Since you say the minus side of the coil is only .26 volts it means the coil windings are either open or the minus side is being grounded somehow. If the coil gets hot when the ignition is turned on for a bit then there is a ground problem. GDs advice about the tach wire is correct. It sounds like the wiring to the minus side of the coil is not correct.

Good job. Thanks for the feedback.