98 Expedition alt overcharged electrical sys
gw1989
08-09-2005, 11:09 PM
Car was overcharging the electrical system while driving. Made it home but then headlights blew out. The next morning we started the car and disconnected the battery to test the alt and the charge went way down and the car hesitated but did not die. We also saw small amount of smoke from steering column and immediately turned off the car. We took alt and battery in and they tested bad (the alt worked but voltage regulator within the alt quit). We replaced with new alt and battery then replaced all blown fuses and still have no power windows, windshield wipers, dome lights and a few other small things.
any help would be appreciated cuz our next step will be a shop and that will be expensive.
any help would be appreciated cuz our next step will be a shop and that will be expensive.
ctesla
08-11-2005, 02:13 PM
when all our grandfathers yanked a battery cable is was to insure the generator was giving power to the battery, any assecories on the car, truck, or tractor, and to isolate the problem of not being a dead cell in the battery.
your Expedition (like all new vehicles) have multiple computers, harnesses, digital dashes/displays, feedback sensors, electronic goodies galore. a "spike" or discharge (or interupting the complete circuit)of that inticate system can be BAD at best.
the voltage regulator inside your alt. probably died out, thereby not 'regulating' the amount of electric charge to put back into the battery or system.
the smoke from the steering column??? hopefully just the start of cooking wires, if you caught it in time.
if the fuses are good, check the relay box;
you have larger 'maxi-fuses' and relays that control the wipers, lights, windows, A/C, ignition, fuel pump, etc.
switch out identical relays to see if they are bad (example: horn works, pull relay, and trade with A/C (if same) fan, borrow fuel pump relay, trade out to window relay (with vehicle ignition on, engine not cranked and not running)) if this solves your problem, go buy relays and relax.
if not, you might have smoked some wiring or possibly a fusible link (if Expiditions have these)...
good luck,
hope its minor,
ctesla
ASE cert.instructor
your Expedition (like all new vehicles) have multiple computers, harnesses, digital dashes/displays, feedback sensors, electronic goodies galore. a "spike" or discharge (or interupting the complete circuit)of that inticate system can be BAD at best.
the voltage regulator inside your alt. probably died out, thereby not 'regulating' the amount of electric charge to put back into the battery or system.
the smoke from the steering column??? hopefully just the start of cooking wires, if you caught it in time.
if the fuses are good, check the relay box;
you have larger 'maxi-fuses' and relays that control the wipers, lights, windows, A/C, ignition, fuel pump, etc.
switch out identical relays to see if they are bad (example: horn works, pull relay, and trade with A/C (if same) fan, borrow fuel pump relay, trade out to window relay (with vehicle ignition on, engine not cranked and not running)) if this solves your problem, go buy relays and relax.
if not, you might have smoked some wiring or possibly a fusible link (if Expiditions have these)...
good luck,
hope its minor,
ctesla
ASE cert.instructor
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