No Speed Control

[George Jones]

I have a 1996 Explorer XLT 4.0. Earlier this week after I parked and turned off the ignition, the horns began to sound. It began as a low hum, then all out non stop honk. I was not able to locate the horns soon enough to avoid the resulting problem, but I eventually found and disconnect the wires at each horn. I noticed a burnt electrical smell in the area of the horns and battery area. I assumed I just needed new horns.

The next day while driving on the interstate, I discovered that my speed control system no longer worked. Nothing at all as if a power supply interruption. What I found while checking fuses is that the pcm/horn fuse in the power distribution had failed. I replaced the fuse, but still no speed control. I have checked fuses through out and they seem to be fine. I would appreciate it if somebody could provide insight. Also, there is what appears to be a fuse box next to the battery on the compartment wall.

 

[Tedybear]

I'm guessing as our 95' is not on the road yet (and our cruse doesn't work either)

Ford and most companies use a main fuse and relay panel. If memory serves it should be a few inches from the battery. From the sounds of the horn issue, one of the relays shorted out. That would explain the horns sounding a bit soft..and then as the contacts start to short together more it would get louder. I would suggest removing the relay for the horn and checking for plastic that looks a bit melted or wires going into that part looking green and crusty.

This is all guess work on my part. If this was a Bronco II I could just about tell you color codes and part locations. (our 95 will be replacing that one)

With any burning electrical smell this is where the visual inspection will likely point you in the right direction. Considering the horn issue, I'd be weary of that relay area and would check for a burnt up relay. I do not know the layout, but if there's anything else in that area that controls the cruse system? Possible damage could also present.

I'll be keeping an eye on this one as well. This is our first Explorer and the more information we can garner? The better for when it goes on the road.

S-

 

[George Jones]

More information;
I spoke with a service tech at Pep Boys who suggested a separate ECU for the speed control, horn, and all safety features. This keyed my mind, and I started checking the safety features for proper operation. The result is that I have a complete failure of all safety features.

There is a long narrow box next to the battery with a large wire harness including many wires. This is what I have riddled out; Of late, the cars factory alarm system has been setting off without need. I now believe the alarm relay failed and damaged everything in the safety ECU, hence the burnt electrical smell at the battery location. It seems that the horn/pgm fuse in the power distribution box is the primary to protect the the remainder of the car's electrical system. I have to make time to open that box and hope the damage is not expensive.

 

[Tedybear]

That long narrow box is what I was referring to. On the BII they called it the "Power Dist Center". Lots of wires going into it, heavy fuses as well. You might have just a blown fuse, or wiring damage considering the burnt smell.

I'd still remove each fuse one at a time and examine the plastic where the fuse plugs into the box for melted plastic. More likely you will need to remove that box and flip it upside down to see the underside of it to fully examine the wires. On the BII that only contains fuses. On the Explorer it might contain fuses and relays. I've not opened ours yet (we have a dead horn and no speed control on ours.....This is why I'm keeping an eye on this.....)

S-

 

[George Jones]

This box is exactly next to the battery attached to the wall along side the battery. It is difficult to access. What is called the power distribution box in the car's operating manual is by the brake master cylinder. I believe that box which is next to the battery contains the safety feature fuses and relays, and the problem. I will post what I find.

George

 

[George Jones]

It seems that the problem is with the factory anti theft system. If I lock the car using the electric system, it engages the alarm system, and then sometime later the anti theft sets it's self off. This happens every time. So now I manually lock each door. For now that is working.

The speed control is now working. So obviously there is some odd problem. I would like to disable the alarm system, but it is embedded in every safety feature.
I removed the main anti theft relay, but then the car would not start. So I don't know what to do. It would be nice to lock the car electrically without engaging the anti theft system. But how?

 

[toypaseo]

How good/old is your battery?

When one of my part batteries was failing, the factory alarm would go off at random times. Never happened again after replacing the battery.

 

[George Jones]

No speed control.

New heavy duty battery, new alternator. Could a failing electric door lock do this?
Or dust in the lift gate electric lock control?

 

[Tedybear]

It seems that the problem is with the factory anti theft system. If I lock the car using the electric system, it engages the alarm system, and then sometime later the anti theft sets it's self off. This happens every time. So now I manually lock each door. For now that is working.

The speed control is now working. So obviously there is some odd problem. I would like to disable the alarm system, but it is embedded in every safety feature.
I removed the main anti theft relay, but then the car would not start. So I don't know what to do. It would be nice to lock the car electrically without engaging the anti theft system. But how?

That's really odd.

You say "Factory Alarm" system. Does this have the keypad above the door handle? Or just a keyfob set. Kinda wondering due to all the fun we just went through with ours. It states "Ford Alarm System" on the windows and the fob's. But in reality it is an aftermarket installed by the dealership.

S-

 

[George Jones]

Yes, it has the factory alarm with all of the relays here and there. There is a key pad on the driver's door. It probably had a key fob, but I am not the original owner.