Cougar

See if the lights have voltage getting to them while the trouble is happening. If you have voltage at the light then the problem is most likely with the switched ground for the lights.

It sounds like you are on the right track. Some folks have had similar problems like this and it does sound like the ignition switch is at fault here. Check to see if voltage is getting to the plus side of the ignition coil while you are in the START mode. If you don't have voltage in that mode and do in the RUN mode then the switch has a problem. It sounds like the ACC position has a problem also since you stated other things aren't working also. The problem may be the switch contacts are just not aligning correctly.

Well you definitely dodged a bullet on this issue by not getting burned and hopefully the car engine dodged one too.

You are most likely good to go now. The lower charging voltage getting to the battery doesn't really make a significant difference to the other things in the car. The lights aren't as bright or the blower doesn't spin as fast, who cares. If voltage gets below 10 volts that could make some difference to some things. You wouldn't even be able to start the engine if the battery was that low.

If you had been driving the car for some time the engine had to be hot. It sounds to me the coolant level was so low the temperature sensor wasn't reading correctly since no coolant was getting to it. Even the thermostat was staying closed until it got hot enough to let loose the explosion. I have to wonder if there is a head gasket leak that caused coolant level to get low. Watch to see if the level drops down or you see signs of bubbles in the coolant.

When links burn out they burn in the middle of the link. While it can be hard By bending them it is easy to feel and see the difference between a good one and a blown link.

Not the flasher circuit, the charging circuit. The battery wasn't getting the full charging power from the alternator due to the added resistance. So that leaves the battery slightly discharged from what it normally should be. When the alternator speeds up then the added voltage coming from it goes to the accessories.

If the clinking sound you are hearing at times occurs while you are in the START mode then chances are the starter solenoid contacts are worn out. With the trouble you are having it may be a good thing to just go ahead and replace the starter, which has the solenoid built on to it. So that gets replaced also. It would be nice to know if you saw any dash warning lights while the engine was trying to start without the key. If there was any on then that would point to the ignition switch is bad. Otherwise, Gloyale's suggestion might be correct. If the trouble is with the ignition switch I'm sure there are some fuses in the dash panel that could be removed to stop the starter but I'm not sure which one at this time.

Well I don't know how doing what you did changed things. This trouble might come back again but hopefully it stays away. Thanks for the update.

I think you will be okay. If I remember correctly there is a protection diode inside the ECU that helps stop damage for this kind of thing. If you don't know where the links are they are in the small plastic box mounted on the coolant reservoir. You most likely blew out the main black link.

Check the resistance values of each of the sensors while the tank is full and see if each one is indicating the correct resistance value for a full tank. One of the sensors may not be correct. Of course if a incorrect part was used that would change things, like you say.

I would have to think the metal flange that seals to the tank is grounded.

Intake manifold gasket failures are pretty common for these models. Use some WD-40 around the gasket seal while the engine is running to see if that shows a air leak up by changes in the engine speed.

The alternator case is grounded to the engine so touching another ground to it isn't going do anything. If the alternator is fairly old then fixing just this problem is just basically a bandaid as it most likely needs a whole rebuild. Get yourself a good rebuilt or used replacement unit. That's my advice anyways. It is a lot easier than trying to repair it. Either way the unit has to be removed from the car. Be sure to remove the battery ground wire first before working on the alternator. The main alternator wire is hot to the battery and sparks will fly if it gets shorted to ground with the battery connected.

The fusible links that are located inside the small plastic box mounted on the coolant reservoir is another area that can cause this trouble. Check for loose connections to the links. The underside connections also.

Well it seems you have proved the wiring to pin 1 is okay. Manually grounding that wire should turn on the warning light. When the alternator isn't running and the ignition is on then pin 1 should be at ground potential through the alternator circuit and the warning light turned on. It appears that isn't happening so check the voltage on pin 1 with things connected normally and see if you see voltage there. You most likely will since the warning light isn't turning on and something inside the alternator isn't right.

Sounds like you got it taken of.

Glad you got it fixed. Thanks for the update.

I think there are two sending units used and it sounds like one of them is showing near empty. I think the sensors are in series with each other if I remember correctly.

That's some good info Ivans Imports. I thought that ECC was for the computer. I'll bet you are correct about the choke and that is what is causing the short.

Well the door switches just switch a ground connection so if one of the wires to the switch was shorted to ground all it would do is keep the dome light turned on. If there is a problem in that area it has to be in the power supply wire to the dome light.

The circuit is directly shorted between the power supply, which is the opposite condition of an open circuit. Since the brake light circuit is switched on that means that it is not causing the trouble unless the brake switch is bad and that is doubtful. Some folks have had problems for the lights up in the roof area. To verify the ECC isn't the cause of the trouble you can disconnect it to see if the trouble clears. It should be above the steering column and is a rectangular box. You would be wise in getting the factory service manual for the wiring on this vehicle to help you locate the problem. It will show you how things are wired and where to locate connections in the car. Ebay is a good place to find one. It would also be helpful I think if you made a test light using a brake light and a bad fuse. By soldering the two lamp wires to each side of the fuse you can insert the old fuse in the fuse panel and the light should turn on bright due to the short on the line. The resistance of the lamp will keep the current flow to the short to a safe level so the wiring won't get damaged. When you find the short and disconnect it then the test light will go dim or turn off. This will save you from blowing a lot of fuses. You can also use an ohmmeter to checked the resistance to ground on the PROTECTED side of the fuse panel, not the power side. The resistance will be very little due to the short until it is removed. As a guess I would think the trouble may be in the roof area. Since disconnecting the ECC is pretty easy I would start with that just to verify it.

If the fuse doesn't blow out until you press the brake pedal then the trouble is with the brake light circuit. If it blows without stepping on the brake then something else is causing the trouble. The ECC is the engine control computer but I doubt it is causing the problem though it is possible. If there is a wire harness for a trailer that is a logical trouble area. If the brake circuit is causing trouble check for shorted wiring inside the sockets for the bulbs. Isolating the connections and replacing them one at a time will show up the bad one if that is the case.

If the fan trouble looks to be from the relay due to low voltage at the motor check the relay socket for heat damage due to a bad connection. The headlight trouble could be due to a bad connection to the power supply lead in the light socket. Check for signs of burning there also.

No, it ties to the ECU which controls the exciter, I believe anyways.