Hi. I just bought a 1995 full size Bronco and it came with electrical problems. The door locks sometimes work with the key, sometimes they don't. The interior door lock switches work fine. The tailgate window doesn't work by its dash switch or key. The electronic 4x4 doesn't work by its dash switch. Half of the dash warning lights don't light up when you turn the key (the owner manual says they should all light up). The passenger door interior light lites up dimly when the door is opened (the driver door's light is bright). I checked the fuse box and power distribution box under the hood. All of the fuses in the fuse box have power except for #10, which calls for a 4 amp fuse - my manual says this fuse is for instrument illumunation, but my instruments do lite up. All of the fuses in the power distribution box have power, except for #s 6 and 7, which my manual says are 10 amp fuses for the trailer lights. I don't know how to test the diodes, circuit breakers and relay switches in the boxes. I checked all fuses and grounds I could find. Can you think of anything else I can check or replace? Should I buy the electrical troubleshooting book on this truck from Helms Publications for $30? If I need an expert, should I take my Bronco to a Ford dealer, my local mechanic, or an auto electric shop? Thanks. Michael Wampler, Gibraltar, Michigan

 

Wow unless you are made of real $$$$$ I would hesitate to have the problem diagnosed by a dealer. You will be paying $40-65 / hour for them to scratch their head. Purchase a good wiring book and a decent electrical meter....the investment is worth it.

I would start by checking all the connections and look for any modifications that were done to the wires. It is obvious something is wrong. As for your tailgate....it is the #1 Bronco problem and it could be related to all the others too. Search this site and look for the tailgate repair link (OR AIM will post it if you ask nicely). I would start at the tailgate wiring and look for a shorted wire.

Disconnect each wire you find, clean it with emery cloth, clean the contacts, and re-attach. The WORST posssible scenario I can think of is that your computer has some internal problems and it is raising hell with the system.


Good Luck.

Bob

 

[updated:LAST EDITED ON 09-Feb-02 AT 03:57 PM (EST)]Hi. I just bought a 1995 full size Bronco and it came with electrical problems. The door locks sometimes work with the key, sometimes they don't. The interior door lock switches work fine. The tailgate window doesn't work by its dash switch or key. The electronic 4x4 doesn't work by its dash switch. Half of the dash warning lights don't light up when you turn the key (the owner manual says they should all light up). The passenger door interior light lites up dimly when the door is opened (the driver door's light is bright). I checked the fuse box and power distribution box under the hood. All of the fuses in the fuse box have power except for #10, which calls for a 4 amp fuse - my manual says this fuse is for instrument illumunation, but my instruments do lite up. All of the fuses in the power distribution box have power, except for #s 6 and 7, which my manual says are 10 amp fuses for the trailer lights. I don't know how to test the diodes, circuit breakers and relay switches in the boxes. I checked all fuses and grounds I could find. Can you think of anything else I can check or replace? Should I buy the electrical troubleshooting book on this truck from Helms Publications for $30?

Thanks Bob.
Michael,
I'm having a bad day w/a stomach virus so, I havent been able to concentrate on the Chilton's wiring diagram I have here (it sux..not much info on fuse box/distr box wiring/schematics).


As a guess, I do think you have a bad ground problem associated w/interior lighting, etc. mainly due to what you stated..."door interior light lites up dimly..." I've seen this in headlight problems.

As for the t'gate, a quickie is to look at the driver's side section of the t'gate and see if it is closed fully. There is an interlock switch in there on the latch. Try pushing on the gate in that area.

or......
JBronco has a post in this MB earlier this week on how he cleaned the driver's t'gate switch. It includes info offered by others here on various t'gate window problems/ repairs.


Earlier today, I posted Chris's t'gate wiring schematic in another post. It gives a good view of the system exc for the aforementioned latch switch.
.....
additional:
I just looked at a Haynes manual; the wiring diagram is a little better than the Chilton's, but is off in the fuse numbers (it states fuse D is for the trailer relay in the pow. distr. box).
and here is Chris's t'gate wiring schematic:
http://www3.telus.net/cbradley/tailgatepowerwindowschematic.JPG

 

Thanks for the suggestions. I'm waiting for my Haynes manual to arrive from an ebay seller, so I have no schematics to look at yet. My initial thinking is that there were too many electrical problems for them to be isolated problems, and that one integral componet or ground was the problem. From your advice, I may have many small problems that need to be fixed one by one. I'll work on it myself for awhile. How do I test the relay switches near the power distribution box, to make sure they're not the problem? Thanks.

 

Your problems all sound seperate and not related to one common cause. The lock problem sounds like it is a problem with the transmitter or receiver for the remote, since the inside switches work fine. Try cleaning the contacts on the remote and putting in a new battery. The rear window is probably something simple like the dashboard switch or the connector at the tailgate. The passenger door light being dim sounds simple, like the bulb, or a wire corroded or coming out of a connector partially. Trace the light, starting at the bulb. Since the driver's is bright, this does not sound like a whole truck ground problem. Not sure about the dashboard lights, some of them don't light up regardless of what the manual says. Which ones are they, and we can check to see if ours do. Also, they have little bulbs in them which can simply go out, so check them. They are relatively easy to get to by removing the instrument cluster. I have a manual transfer case (Thank God!) and I have no experience with the electronic ones. But again it is probably a simple thing. Get yourself a cheap multimeter and start tracing this stuff down. You could probably fix most of it for free in an afternoon. Most used Broncos have these problems, on mine I had to fix the rear window and a power door lock on the driver's side.

 

Thanks JBronco. You gave me something new to look into on the exterior lock problem. I didn't get a remote with the truck, only the ignition key. I had a locksmith make the tailgate key from the glovebox lock. It turns the tailgate lock easily both ways, but nothing happens with the window - neither the key or dash switch works the tailgate window. I'll check with the parts guys at my local Ford dealer to see if I can buy a replacement remote, and whether this would fix the exterior door lock problem. That's my biggest concern right now, so I can start locking up the truck. Thanks.

 

You were not talking about the locks working with a remote? I don't understand what you meant about the locks working with the key and sometimes not. I have a 90. Did you mean that on yours, the key locks and unlocks both doors? Even so, I still think it is a seperate problem. Yours may not have had a remote then.

 

PS- if you meant simply that the key does not work the lock, it has nothing to de with electrical and would be a problem with the linkage of the key and lock. Take off the door panel and check it out. Sometimes the linkage has a spot where it binds and won't let the linkage move all the way intermittently. Check for motion a few times and see if it binds, also oil it while you are there and spray some oil into the key cylinder.

 

I recommend Graphite grease be used in a door lock.

Not oil.



Dennis



Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"


78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon

 

[updated:LAST EDITED ON 10-Feb-02 AT 02:33 PM (EST)]"...Half of the dash warning lights don't light up when you turn the key (the owner manual says they should all light up)..."

I just checked our 96 Bronco (no tachometer); when I turned ign key to "ON" (not to Start; Engine is off), the following warning lts. appeared briefly:
Check Engine (upper left side)
ABS (lower left)................................BATTY (lower right)
........................
Then, with key still in ON; the ABS light shut off and the Airbag light lit (in lower section, to the right of the left turn ind. lt)

Safety Belt Warning lt - upper right
.....................

I read the Owner's Guide and it is quite detailed about when some warning lt.s are lit and why some are not lit in diff. key positions.
i.e.: "...Anti-Lock Brake System Warning Light - To check the amber ABS brake warning light turn the ignition key to ON. The ABS brake
warning light should glow momentarily.
NOTE: If it does not glow momentarily, have your vehicle’s electrical system checked immediately..."
--
and,
"Safety Belt Warning Light and Chime - This warning light and chime remind you to fasten your safety belt. The following conditions
will take place: If the safety belt is not buckled when the key
is turned to the ON position, the light comes on for 1 to 2 minutes and the chime sounds for 4 to 8 seconds.
If the safety belt is buckled while the light is on and the chime is sounding, both the light and chime turn off.
If the safety belt is buckled before the ignition is turned to the ON position, neither the light nor the chime will come on."
--
"Check Engine" - "The light comes on briefly when you turn the
ignition key to ON, but it should turn off when the engine starts. If the light does not come on when you turn the ignition to ON or if it comes on and stays on when you are driving, have your vehicle serviced as soon as possible. This indicates a possible problem with one of the vehicle’s emission control systems. You do not
need to have your vehicle towed in."
--
Charging System Light - "This light comes on every time you turn the
ignition to the ON or START position (engine off). The light should go off when the engine starts and the alternator begins to charge.
If the light stays on or comes on when the engine is running, have the electrical system checked as soon as possible."
--
Supplemental Air Bag Readiness Light and Tone Generator -
"This light illuminates for six seconds when the ignition is turned to the ON position. If the light fails to illuminate, continues to flash, remains on, or if a series of five beeps is heard, have the
system serviced as soon as possible."
--

 

I guess I wasn't clear about my door lock problem. I don't have a remote and haven't tried one. When I turn the key in the driver side exterior door lock, sometimes it will unlock the door (I see the button come up), but most the time it won't unlock the door, and it NEVER locks the door. If I use the interior switch for my door locks, everything works fine - I see the button moving up and down as I press the interior switch. Do you think it still may be related to me not having a remote? Can the remote (or lack of one) affect the exterior key locks? Thanks again for all the useful advice.

 

Door locks should Lock/Un-Lock (that particular door)with the key.
It's Called: manual overide locking system

Dennis



Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"


78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon

 

Forget about the remote, I didn't understand your problem with the locks. The problem is with the linkage between the key cylinder and the locking mechanism. It is seperate from where the power door lock actuator is connected to the locking mechanism. Should be an easy fix, although it is hard to get your hands in there and to see what you are doing.

 

The first thing I would check for the tailgate problem is whether your tailgate is closing all the way. If your tailgate doesn't latch completely, neither the switch or key will work. You may have to adjust the latches in order for them to seat fully. I had this trouble with my Bronco after I first got it.

If that isn't the case, then I would suspect a bad connection in the tailgate, or in the circuit that applies power to the tailgate.