98 ford explorer sport 4x4 lights flashing

[RALPH Florio]

My 4x4 lights started flashing today. I have seen on a few sights that it could be the accessory delay relay, or a hall sensor. Among other things. I would like to start with the relay first, but I have no clue where it is. I have heard that a lot of others who have had this problem also lost their power windows. Of course I didn't know that before so I didn't check. I will say that it just hit me that I did replace a front tire today, could that be a factor?

 

[96eb96]

Hi Ralph,
Tire could be a coincidence, but all those features are controlled by a computer called gem that I believe is to the left of the radio when you remove it.

You can try this;
remove the radio, and reseat the connector to the gem. sometimes the contacts go bad. search the forum for more information.

Next you can download an app called forscan, install on your pc and it will give you more information than the dealer. you have to go on amazon and buy an adapter (search for bafx, it is about 20 bucks). this uses bluetooth. Forscan itself is free.

only very expensive scan tools can read the gem computer, so if you don't take the above route you can either guess or take it to the dealer. Once you have the trouble codes post them here and we can go further. Forscan can also monitor exactly what the gem sees, so you can pinpoint for example if your selector switch is working.

 

[XLTrunner]

Also, one thing you need to know with your '98 is that you can't just replace one (or, even two) tires without the risk of throwing off the readings from the Hall effect sensors. All four tires MUST be of the same actual diameter (not just the same make or size) within 3/32" of each other. This is the dirty little secret to owning a Control Trac or AWD...you can't just replace a tire or two at a time like in the old days without confirming that the replacement tires are within recommended diameter compared to remaining tires. Don't know if this will trigger the 4x4 lights to flash, but it WILL wreak havoc on your transfer case in due time since, unlike previous years, you cannot completely disengage your 4x4 (unless you do the infamous "brown wire" conversion). Even in Auto mode, a small percentage of torque is being applied to the front wheels at all times.

 

[96eb96]

Also, one thing you need to know with your '98 is that you can't just replace one (or, even two) tires without the risk of throwing off the readings from the Hall effect sensors. All four tires MUST be of the same actual diameter (not just the same make or size) within 3/32" of each other. This is the dirty little secret to owning a Control Trac or AWD...you can't just replace a tire or two at a time like in the old days without confirming that the replacement tires are within recommended diameter compared to remaining tires. Don't know if this will trigger the 4x4 lights to flash, but it WILL wreak havoc on your transfer case in due time since, unlike previous years, you cannot completely disengage your 4x4 (unless you do the infamous "brown wire" conversion). Even in Auto mode, a small percentage of torque is being applied to the front wheels at all times.

My 96 has a true 2wd mode, but that was the last year. Limited slip diffs also hate different size tires.

If the vehicle gets is speed from the abs system, this Front size difference could be a reason for concern. I thought (on my 96) vehicle speed comes from the transmission.

 

[XLTrunner]

Yea...I don't know what genius at Ford thought it was a good idea to eliminate the true 2WD option mode. I owned a '95 prior to my '98 and didn't realize it until after I bought it.

Can't remember on the '95...but, on the '98, there are two Halls effect sensors on the transfer case and one on top of the rear diff housing to monitor/compare axle speeds.

 

[RALPH Florio]

Also, one thing you need to know with your '98 is that you can't just replace one (or, even two) tires without the risk of throwing off the readings from the Hall effect sensors. All four tires MUST be of the same actual diameter (not just the same make or size) within 3/32" of each other. This is the dirty little secret to owning a Control Trac or AWD...you can't just replace a tire or two at a time like in the old days without confirming that the replacement tires are within recommended diameter compared to remaining tires. Don't know if this will trigger the 4x4 lights to flash, but it WILL wreak havoc on your transfer case in due time since, unlike previous years, you cannot completely disengage your 4x4 (unless you do the infamous "brown wire" conversion). Even in Auto mode, a small percentage of torque is being applied to the front wheels at all times.

OK THAT WOULD HAVE BEEN GOOD INFORMATION TO HAVE WHEN I BOUGHT THIS TRUCK. BECAUSE I HAVE HAD UNMATCHED TIRES ON THIS TRUCK FOR THE LAST50 K MILES!! BUT THE BRIGHT SIDE OF THAT IS I THINK I AM GOING TO TRY PUTTING TWO MATCHED TIRES ON THE FRONT. I STILL HAVE NOT BEEN ABLE TO FIND OUT FROM ANYONE WHERE THE ACCESSORY DELAY RELAY IS? I HAVE A QUESTION REGARDING THE SMALL TOLERANCE YOU QUOTE FOR TIRE INEQUALITY, THAT WOULD MEAN AN AIR PRESSURE DIFFERENCE OF APPROXIMATELY TEN POUNDS WOULD CAUSE THE SAME THING, THAT CAN'T BE RIGHT

 

[XLTrunner]

Oh, it IS right! They are adamant about maintaining equal tire pressure as well as worn suspension parts needing to be replaced as they can have an adverse effect, too. I learned that the hard way. I was diligent about rotating the tires, but let the ball joints get sloppy and $800 dollars later, was the proud owner of a rebuilt transfer case. And, did I mention I never touched the dash switch in the 50K miles prior that I owned it? Can only surmise that the worn suspension must have had something to do with it as the fluid was still good and the sensors were fine.

 

[RALPH Florio]

Oh, it IS right! They are adamant about equal tire pressure as well as worn suspension parts needing to be repaired as they can have an adverse effect, too. I learned that the hard way. I was diligent about rotating the tires, but let the ball joints get sloppy and $800 dollars later, was the proud owner of a rebuilt transfer case. And, did I mention I never touched the dash switch in the 50K miles prior that I owned it?

The suspension being a factor is pretty funny since every explorer I have ever seen has a sagging rear suspension.!!!

 

[96eb96]

Yea...I don't know what genius at Ford thought it was a good idea to eliminate the true 2WD option mode. I owned a '95 prior to my '98 and didn't realize it until after I bought it.

Can't remember on the '95...but, on the '98, there are two Halls effect sensors on the transfer case and one on top of the rear diff housing to monitor/compare axle speeds.

Cost is the reason. There is a center axle disconnect. I usually run in 2wd unless there is inclement weather or offroad. Saves wear and tear on the systems. Probably save a mpg.

Rear diff tone ring is also for the ABS system. Had to install it when I did my trac lok

Expeditions have 4 settings.