GEM Swapping On Stock 99 Explorer EB?

[Rabbit Heart]

Hi everyone, first time posting a question so my apologies if I am in the right place. I read through several threads but couldn't quite find an answer to my problem.

My 99 Explorer EB has a battery drain. Took it to a mechanic after trying to sus it out myself, and $275 later he says the entire GEM module is faulty and needs to be replaced.

Now, I'm no professional, but I haven't had a single code related to the GEM (or at all), all the electronics work just fine. No issue with losing battery while driving, only that on startup after being parked for a day or two it is near dead.

Only consistent issue I have had is that I am getting the 'key in ignition' ping once I open my door. When he took out my GEM to diagnose the issue and put it back in, I had no problems (and no ping) for two weeks. But now the 'key in ignition' ping is back, and after not driving this weekend when I went to start my girl up the battery light was on.

My question is three fold:

1. I understand that I need to purchase a GEM of the same year as my car. However, does the 'edition' matter? What about the engine? Do 99 Explorers have the annoying programming issue where you have to reset the GEM if transferring to a different Explorer?

2. Is it safe to purchase one from Ebay? Some are for sale for $30 and others over $100. I'd rather purchase from a trustworthy individual if anybody knows someone who might be selling one.

3. How easy is it to replace a GEM in this model? Is it something an amateur could do, or is it best to leave up to the professionals?

Thank you kindly for your time!

 

[donalds]

Hi everyone, first time posting a question so my apologies if I am in the right place. I read through several threads but couldn't quite find an answer to my problem.

My 99 Explorer EB has a battery drain. Took it to a mechanic after trying to sus it out myself, and $275 later he says the entire GEM module is faulty and needs to be replaced.

Now, I'm no professional, but I haven't had a single code related to the GEM (or at all), all the electronics work just fine. No issue with losing battery while driving, only that on startup after being parked for a day or two it is near dead.

Only consistent issue I have had is that I am getting the 'key in ignition' ping once I open my door. When he took out my GEM to diagnose the issue and put it back in, I had no problems (and no ping) for two weeks. But now the 'key in ignition' ping is back, and after not driving this weekend when I went to start my girl up the battery light was on.

My question is three fold:

1. I understand that I need to purchase a GEM of the same year as my car. However, does the 'edition' matter? What about the engine? Do 99 Explorers have the annoying programming issue where you have to reset the GEM if transferring to a different Explorer?

2. Is it safe to purchase one from Ebay? Some are for sale for $30 and others over $100. I'd rather purchase from a trustworthy individual if anybody knows someone who might be selling one.

3. How easy is it to replace a GEM in this model? Is it something an amateur could do, or is it best to leave up to the professionals?

Thank you kindly for your time!

Or start by saying this I don't think you're GEM is the problem I have never seen 1 go bad I've seen people replace them but not a bad unit
I think you have a battery issue I think you need a new battery or Dirty terminals........
There is no programming involved I think the V6 in V8 may have different program programming but according to the service manual they are the same 4 wheel drive or 2 wheel drive is the only difference
I suggest you go to the junkyard and get 1 yourself

Installing it is just a matter of removing the radio basil and the radio the GEM is right there

Here's a few pictures of the gem module
By the way I own a 99 myself

 

[Fix4Dirt]

in my 98 iirc they can swap over only thing that varies is 4x4 vs 2wd and then programming specific options like speed sensitive wipers. i thik thr v8 programming may have been different if it was awd, but donalds knows more than i so hes probably right its super easy to change, as he mentioned. i usually stray from online sources when finding stuff like this, id rather get one off a JY one usually

 

[Rabbit Heart]

Or start by saying this I don't think you're GEM is the problem I have never seen 1 go bad I've seen people replace them but not a bad unit
I think you have a battery issue I think you need a new battery or Dirty terminals........
There is no programming involved I think the V6 in V8 may have different program programming but according to the service manual they are the same 4 wheel drive or 2 wheel drive is the only difference
I suggest you go to the junkyard and get 1 yourself

Installing it is just a matter of removing the radio basil and the radio the GEM is right there
View attachment 434078


View attachment 434079

View attachment 434080

Here's a few pictures of the gem module
By the way I own a 99 myself

Hi Donalds, thank you so much for your thoughtful reply!

I agree, I also don't think it's a 'faulty GEM'. I had a bit of a rough experience with this mechanic, where I was trying to ask questions (ie is it a specific circuit that's out?) but I was sort of... well... treated like I didn't know an axle from a shaft. But I figure if I can get a replacement for $30 it's worth a shot.

Thank you for the great advice! I just replaced the battery, so I will try giving the terminals a scrub and see if that helps.

 

[Rabbit Heart]

in my 98 iirc they can swap over only thing that varies is 4x4 vs 2wd and then programming specific options like speed sensitive wipers. i thik thr v8 programming may have been different if it was awd, but donalds knows more than i so hes probably right its super easy to change, as he mentioned. i usually stray from online sources when finding stuff like this, id rather get one off a JY one usually

Thank you Fix4Dirt for the advice! I will call around to see if I can find a junkyard. Unfortunately I'm kinda in the middle of nowhere, so hopefully I can find one at least in my state!

 

[donalds]

$30 it's worth a shot

Yes
There is a free program called Forscan with a $15 USB elm327 odb 2 connector
This will allow you to test all of the GEM functions 1 at a time You can run self test and everything the ford dealer can do to test this thing

You will also have access to all other modules including the power train control module with this program it's great

 

[CDW6212R]

The Forscan and the required device to connect it is a great tool for most Fords of the mid 90's and newer. I have one but haven't begun to explore the many things it can do.

BTW, for the 99 the GEM should be any one from 1998-2001 Explorers, matching the 4WD or not 4WD models. The AWD is the same as 2WD in the GEM's, because AWD has no electrical functions.

The same goes for early 2nd gen's, the 1995-1997's should have two possible GEM modules, with or without 4WD. It would be smart to buy a spare for every Explorer you own, the electronics are old and are hard to repair or replace etc.

 

[Mbrooks420]

in my 98 iirc they can swap over only thing that varies is 4x4 vs 2wd and then programming specific options like speed sensitive wipers. i thik thr v8 programming may have been different if it was awd, but donalds knows more than i so hes probably right its super easy to change, as he mentioned. i usually stray from online sources when finding stuff like this, id rather get one off a JY one usually

I believe all the V8s would be the same. As far as the truck knows they’re all 2wd, since the AWD is entirely mechanical.

 

[Rabbit Heart]

Yes
There is a free program called Forscan with a $15 USB elm327 odb 2 connector
This will allow you to test all of the GEM functions 1 at a time You can run self test and everything the ford dealer can do to test this thing

You will also have access to all other modules including the power train control module with this program it's great

Thank you so much! I'm going to buy one of these tonight! I searched up what you said and found this: Amazon link

I'm going to buy it tonight! Thanks again!

 

[C420sailor]

You won’t regret it. Forscan is amazing

 

[Rabbit Heart]

The Forscan and the required device to connect it is a great tool for most Fords of the mid 90's and newer. I have one but haven't begun to explore the many things it can do.

BTW, for the 99 the GEM should be any one from 1998-2001 Explorers, matching the 4WD or not 4WD models. The AWD is the same as 2WD in the GEM's, because AWD has no electrical functions.

The same goes for early 2nd gen's, the 1995-1997's should have two possible GEM modules, with or without 4WD. It would be smart to buy a spare for every Explorer you own, the electronics are old and are hard to repair or replace etc.

This is great advice, thank you so much! I appreciate the detailed reply. I only have the one (Dora) and she is a hand me down but I want to make sure I keep her in great shape! She's definitely a workhorse!

 

[CDW6212R]

You are very welcome. The trick with these is learning what parts will swap between different years and models. The newer cars are much harder to work with at home, the 90's stuff are among the last that are easy to own and work on etc.

 

[blakshukvw]

You could just conduct a draw test yourself. Use a test light or a volt meter between the battery ground post and the battery negative cable. With a volt meter, set it to amps. Then just start pulling fuses until the light dims all the way off or your amp draw is eliminated. Then youll have to determine on that circuit what is the draw. From there it’s just as easy to start unplugging those consumers.

 

[410Fortune]

the v6 trucks 97-01 the GEM is also the 4x4 control module, TOD controller

You CANNOT use the gem from a v8 truck as they never had the 4x4 control module inside the GEM

Your "key in chime" is likely a simple fix , the wire at the ignition lock cylinder gets out of place and ground when it is not supposed to. Remove steering wheel column upper and lower shroud and have a look see.

 

[CDW6212R]

There is a separate 4WD module and TOD module for the 2nd gen Explorer 4x4's that had A4WD; so a matched set of three modules to operate the Control Trac system.

 

[efBrianM]

My neighbor had a similar problem with his Expedition ('08 iirc) The battery would be drained down if it set for a couple of days. Start it up and drive it every day, no problems. I hooked up my handheld meter as blakshukvw mentioned, to measure current. The vehicle would cycle between a low current value and a draw of approximately 5 amps (can't remember the exact value). The 5 amp reading would last about 5 seconds, and the near zero reading would last a minute or two. The vehicle would cycle like this continually. I left my meter with him and told him to start pulling fuses, maybe 3 at a time. Turned out to be related to some kind of electronic latch on the glass in the liftgate. The mechanical part of the latch was all gummed up with dirt and would not rotate far enough and the electronics would continually try to "latch" the glass. He cleaned up the mechanical part, problem went away.

 

[efBrianM]

the v6 trucks 97-01 the GEM is also the 4x4 control module, TOD controller

Would this statement be true for my '95 v6, or is the 4x4 control module and TOD controller separate?

 

[CDW6212R]

Would this statement be true for my '95 v6, or is the 4x4 control module and TOD controller separate?

They all have a separate 4WD module, the TOD module began with the Control Trac feature, which was 1996 I think(the dash 4WD switch changed from 2WD left most position, to the A4WD choice).

 

[Mbrooks420]

They all have a separate 4WD module, the TOD module began with the Control Trac feature, which was 97 I think(the dash 4WD switch changed from 2WD left most position, to the A4WD choice).

Pretty sure ControlTrac started in 95. My 96 had auto 4wd.

 

[CDW6212R]

Pretty sure ControlTrac started in 95. My 96 had auto 4wd.

Okay so the 95 was the only one with 2WD and the vacuum controlled front diff/disconnect, I forget these details.