95 Ranger Electical Issue

[herbi]

My 1995 Ranger experienced failure of windshield wipers, speedometer, odometer, interior dome light, 4wd. I believe it all happened at the same time. I think I may have had this happen 20 years ago and maybe it was a relay, but unsure if it's exactly the same. Does not seem like this would all be on a single fuse. I have looked at fuse/ relay diagrams, but don't see anything that it might be. Thanks for any suggestions. This truck has always had funky electrical. When new the door chime would stick on when it got hot and my car stereo was stolen and so I had to listen to this door chime constantly alone on a 5 hour drive. Good times.

 

[RonD]

Welcome to TRS

Not related
Speedometer/odometer are electric in 1995(first year) both share one signal from a VSS sensor on transfer case tail shaft
VSS is gear driven like a speedometer cable setup
Check its 2 wires unplug and plug back in
Fuse 24 in cab fuse box is for speedometer, 10amp


Does the dome light come on when you rotate the Dimmer all the way up?
If not bulb is burned out
If it does work then problem can be a few things.
Door switch, does Dome light come on when passenger door is opened?
Does the Door Ajar light on the dash come on with door open?

The Chime would come on if key was in ignition and drivers door was open, or Door Ajar light was on, which means a bad door switch if chime stayed on all the time, while driving
This is in the GEM module behind the radio

GEM module also runs the wipers
The wiper wiring on the Multi-function switch(turn signal stalk) go to GEM
GEM then activates the wipers via relays in the engine fuse box

Did the wipers just quit one day?
Or did it happen over time where you had to change the switch setting for wipers to work?

 

[herbi]

Thanks for the response. I believe all of these electrical problems are tied to one issue as I noticed them within the space of a few days. Wipers did not respond when I turned them on rather than while using them. A few days later I noticed the other issues. Also an aftermarket 6 CD changer stopped working, but the stereo works. The dome light yes I did adjust the dimmer so it is not that. Being so old maybe it is a short. I do not understand the GEM exactly, but was wondering if it was something there. In the past I had multiple simultaneous electrical failures including speedometer which I believe was a relay. I should probably try looking at those first.

 

[RonD]

Only the Wipers and Dome light use relays and different relays, nothing in common, same for different fuses

Speedometer/odometer each has its own electric motor, but they share the one speed signal from the VSS, there are no relays that would effect cluster

One other thing they have in common is ignition switch under the steering column
When you turn on the key the ignition switch powers several Cab fuse box fuses, in different groups, 2 different groups maybe 3
So pull out a few fuses and test if they have 12v with key on

1995 was an Oddball year for Rangers, much different wiring than 1994 because 1995 got the new 104 wire computer and GEM module
And its not quite the same wiring as 1996

1995 GEM fuses and wiring below

 

[herbi]

Thanks. It sounds like it is probably not anything as simple as I had hoped. I will check out these PDFs.

 

[herbi]

The fuse for the speedometer/GEM was blown and when I replace it the new fuse blew instantly. I am not sure if this gives any clue as to whether it may be something a nonprofessional simpleton could fix.

Only the Wipers and Dome light use relays and different relays, nothing in common, same for different fuses

Speedometer/odometer each has its own electric motor, but they share the one speed signal from the VSS, there are no relays that would effect cluster

One other thing they have in common is ignition switch under the steering column
When you turn on the key the ignition switch powers several Cab fuse box fuses, in different groups, 2 different groups maybe 3
So pull out a few fuses and test if they have 12v with key on

1995 was an Oddball year for Rangers, much different wiring than 1994 because 1995 got the new 104 wire computer and GEM module
And its not quite the same wiring as 1996

1995 GEM fuses and wiring below

 

[RonD]

Whats the fuse number, there are a few for both?

Fuse 25 in cab fuse box powers both full time so if fuse blew with key off then thats the one

You can pull out the radio and then the GEM and unplug its connectors
Then put in another fuse
If it blows then instrument cluster has the short
If it doesn't then GEM has the short

But before replacing either test the wires, with fuse out
On GEM's 18 pin connector White/yellow wire on pins 5 and 11 go to fuse 25
On Cluster's 10 pin connector, pin 4 white/yellow wire runs to fuse 25

OR

Unplug GEM and Cluster connectors
Put in fuse
If it blows then a wire is shorted not the GEM or Cluster
If it doesn't blow then wires are OK

 

[herbi]

yes it is fuse 25 in the cab box and it blew with the key off. I will attempt your suggestions. In the past I am often not very skilled at accessing things in this area, but I will give it a shot. Probably should spend the money to have a pro look at it but being a 95 I am starting to feel like it is aging out of people wanting to deal with it. When I needed body work I had to go to a weird, kinda sketchy semiprofessional place. Anyway thanks again.

Whats the fuse number, there are a few for both?

Fuse 25 in cab fuse box powers both full time so if fuse blew with key off then thats the one

You can pull out the radio and then the GEM and unplug its connectors
Then put in another fuse
If it blows then instrument cluster has the short
If it doesn't then GEM has the short

But before replacing either test the wires, with fuse out
On GEM's 18 pin connector White/yellow wire on pins 5 and 11 go to fuse 25
On Cluster's 10 pin connector, pin 4 white/yellow wire runs to fuse 25

OR

Unplug GEM and Cluster connectors
Put in fuse
If it blows then a wire is shorted not the GEM or Cluster
If it doesn't blow then wires are OK

 

[RonD]

Just a heads up, if its the Cluster that is shorted it can only be replaced with a 1995 cluster, 1994 or 1996 won't work as is

1996-2003 clusters can be made to work but you need to unpin wires on the connectors and re-pin them at different locations

 

[herbi]

I unplugged the GEM and the fuse did not blow so I guess that means a short in the GEM. It seems like ordering a used GEM is the only option. I need to go google some more to cut down on my stupid questions. I did see some videos titled Redneck GEM Workaround and I do live in Idaho...

Now that I read some it sounds like it may be a wiring issue. If only I remember how to use my multimeter.

 

[RonD]

If you are looking for another GEM try: https://www.car-part.com/

Part you are looking for is "Computer Box Not Engine"
Search

New window will open
GEM = Multifunction
Try to match the numbers on yours
(And no you can't add keyless entry with just a different GEM, also need a RAP module and wiring)

 

[herbi]

It sounds like it can be common for the short to be a wire running to the GEM? Given that mine is now 29 years old it seems pretty possible the issue is in the GEM, but I saw a comment elsewhere that the issue is most commonly short to ground on a wire that runs into the GEM. I can see replacing the GEM and still have the issue. I guess the next step is to try to figure out using a multimeter to determine if it is a wire issue. Thanks for answering so many questions.

 

[RonD]

If you unplugged the GEM and the fuse didn't blow then wires from the fuse to the GEM are not shorted, neither are other wires to other components on that one fuse

 

[herbi]

I kind of started to guess that might be the case .

My GEM has F57B-14B205-EH and 941214 and BE2B2753C4 on it. I am thinking the F57B-14B205-EH is the relevant number - however car-part.com does not have any with the EH at the end. I am not sure if one with like an EL would work.

Ebay has a match, but it says it is for a 96 so now I am confused https://www.ebay.com/itm/174684584971 it seems like everywhere I find a match it says it is for a 96. Me and my weird old truck. It may be possible that the dealership replaced my GEM 27 years ago when it was under warranty as it had an issue with the door chimes never shutting off. hmm.

I also did a weird thing when I got the truck. My grandfather worked for Ford corporate upper management and I got the truck as a gift for college graduation so I did a weird custom order that I think delayed the truck and annoyed everyone - it was a 4 liter XLT, but I downgraded the windows to manual windows and locks and some other things. That is all rather boring but am wondering if I ended up with a mismatched GEM to the normal for an XLT. I will look for an EH GEM. Thank you for your patience I have been casual and half assed about the issue over the summer.

 

[RonD]

Use 1996 as the year for car-parts.com search

And see if F57B-14B205-EH comes up, not that unusual
The "F5" means a 1995 part "design" so not only for that one year
1995 parts were used in 1996 and up Rangers