1995 3.0 4WD Problem
#1
1995 3.0 4WD Problem
I drive a 1995 Ranger 3.0 XLT 5 speed
The 4WD and 4WD dash light flash 6 times every 2 minutes or so after I ran new wiring from my dome light to a switch I installed and tapped into the 12v ACC. In the process of doing that I did remove the GEM Module to have more room to work. I never messed with any of the wiring from it, only unplugged it and set it aside and plugged it back in. When I plugged the GEM module back in, I actually got the glovebox/cargo lights to start working again, but now the 4wd lights flash and I'm not sure why.
I've confirmed that everything is plugged in and snug, there are no loose or split wires.
All my fuses are good in power distribution box and interior fuse box
I've confirmed that all 8 relays above the gas pedal are working
I'm not sure what I am missing or what happened just by unplugging and plugging it back I back in.
If anyone has a fix for this or any advice on what to check it would be a big help.
The 4WD and 4WD dash light flash 6 times every 2 minutes or so after I ran new wiring from my dome light to a switch I installed and tapped into the 12v ACC. In the process of doing that I did remove the GEM Module to have more room to work. I never messed with any of the wiring from it, only unplugged it and set it aside and plugged it back in. When I plugged the GEM module back in, I actually got the glovebox/cargo lights to start working again, but now the 4wd lights flash and I'm not sure why.
I've confirmed that everything is plugged in and snug, there are no loose or split wires.
All my fuses are good in power distribution box and interior fuse box
I've confirmed that all 8 relays above the gas pedal are working
I'm not sure what I am missing or what happened just by unplugging and plugging it back I back in.
If anyone has a fix for this or any advice on what to check it would be a big help.
#2
Welcome to the forum
Unhook the battery for 5 min then reconnect if you haven't already
That resets everything
The 4WD lights are flashing because 4x4 controller(GEM in 1995) doesn't know what gear the transfer case is in, 2WD, 4high or 4low
Or it has lost connection to the shift control relay box, should be across from GEM behind radio
The GEM is connected to the dash 4wd switch and the dash lights, and also the shift control module(2 relays in a box)
And its also connected to the 4 contacts in the shift motor
The way it works
When you select 4high, the GEM sees the resistance change in the 4wd switch, it then "sees" where shift motor is at now, 2WD or 4low, by looking at the contact wheel connections on the shift motor.
It then activates ONE of the relays in the shift control module, this either turns the shift motor counter clockwise from 2wd to 4high, or clockwise from 4low to 4high
As the motor turns GEM watches if contacts are opening and closing which means motor is turning, if contacts don't immediately change then GEM will flash 4WD light, not your problem, just an FYI
When contacts are in correct position for 4high GEM opens that one relay to stop motor from turning and THEN it turns on the 4high light on the dash, so there should always be a delay from selection to light coming on, lights are not simply connected to the switch, shift motor must be in correct position before light comes on
Pictures of shift motor here: https://www.explorerforum.com/forums...-motor.123542/
4th picture shows transfer case shift rod in 2WD position
5th and 6th picture show contact wheel and contacts
Best guess from your description is that the Shift control module(2 relays) is unplugged/loose connector, its not that big, 1/2 the size of GEM or less, and I think it has a 10wire connector but only uses 7 wires
Fuse #16(20amp) in engine fuse box powers the shift motor, and GEM monitors that full time 12volt wire, if that fuse is bad then lights would flash
Unhook the battery for 5 min then reconnect if you haven't already
That resets everything
The 4WD lights are flashing because 4x4 controller(GEM in 1995) doesn't know what gear the transfer case is in, 2WD, 4high or 4low
Or it has lost connection to the shift control relay box, should be across from GEM behind radio
The GEM is connected to the dash 4wd switch and the dash lights, and also the shift control module(2 relays in a box)
And its also connected to the 4 contacts in the shift motor
The way it works
When you select 4high, the GEM sees the resistance change in the 4wd switch, it then "sees" where shift motor is at now, 2WD or 4low, by looking at the contact wheel connections on the shift motor.
It then activates ONE of the relays in the shift control module, this either turns the shift motor counter clockwise from 2wd to 4high, or clockwise from 4low to 4high
As the motor turns GEM watches if contacts are opening and closing which means motor is turning, if contacts don't immediately change then GEM will flash 4WD light, not your problem, just an FYI
When contacts are in correct position for 4high GEM opens that one relay to stop motor from turning and THEN it turns on the 4high light on the dash, so there should always be a delay from selection to light coming on, lights are not simply connected to the switch, shift motor must be in correct position before light comes on
Pictures of shift motor here: https://www.explorerforum.com/forums...-motor.123542/
4th picture shows transfer case shift rod in 2WD position
5th and 6th picture show contact wheel and contacts
Best guess from your description is that the Shift control module(2 relays) is unplugged/loose connector, its not that big, 1/2 the size of GEM or less, and I think it has a 10wire connector but only uses 7 wires
Fuse #16(20amp) in engine fuse box powers the shift motor, and GEM monitors that full time 12volt wire, if that fuse is bad then lights would flash
Last edited by RonD; 12-05-2018 at 11:44 AM.
#3
So I should just unplug the battery for 5 minutes to reset it? I kind of thought something like that was the issue. I'll make sure the connections are good and unplug my battery and see what the result it.
I did forget about 2 things that occured while I was wiring my dome light. When the glove box light randomly came on when I was putting everything back together, there was also a weird buzzing sound for a few seconds and then went away and haven't heard it again after that
Secondly, sometimes when I start my truck, I can hear what sounds like relays clicking for a few seconds but then stops. There isn't any consistecy to it either, just sometimes I can hear it, and sometimes I don't.
Would it be a good idea just to replace the 4 relays just in case one of them got fried some how?
I did forget about 2 things that occured while I was wiring my dome light. When the glove box light randomly came on when I was putting everything back together, there was also a weird buzzing sound for a few seconds and then went away and haven't heard it again after that
Secondly, sometimes when I start my truck, I can hear what sounds like relays clicking for a few seconds but then stops. There isn't any consistecy to it either, just sometimes I can hear it, and sometimes I don't.
Would it be a good idea just to replace the 4 relays just in case one of them got fried some how?
#4
The Battery Saver relay in Relay Box 1, the one under the dash to the right of steering column
The GEM controls that relay, it power several things, including glove box light
This relay stays on for about 20-30min after you exit the vehicle, GEM has a timer, when GEM "goes to sleep" it opens that relay in case lights were left on
It could also be the 4x4 relays clicking, on start up the GEM checks 4x4 system as to what position transfer case is in, if contacts were not readable it may move motor back and forth to check position
The GEM controls that relay, it power several things, including glove box light
This relay stays on for about 20-30min after you exit the vehicle, GEM has a timer, when GEM "goes to sleep" it opens that relay in case lights were left on
It could also be the 4x4 relays clicking, on start up the GEM checks 4x4 system as to what position transfer case is in, if contacts were not readable it may move motor back and forth to check position
#5
#6
Update:
i left battery disconnected for around 10 minutes, this didn't fix the issue.
I looked behind my radio but the only thing behind it is the gem Module itself. Nothing on the right side of it.
im not sure if I'm psyching myself out, but I'm almost certain my truck is operating a bit different ever since those lights started flashing. I feel like if I apply a steady amount of gas I can feel it surge or like loss of acceleration for like a split second and it feels like that throughout my drive. It's weird.
i left battery disconnected for around 10 minutes, this didn't fix the issue.
I looked behind my radio but the only thing behind it is the gem Module itself. Nothing on the right side of it.
im not sure if I'm psyching myself out, but I'm almost certain my truck is operating a bit different ever since those lights started flashing. I feel like if I apply a steady amount of gas I can feel it surge or like loss of acceleration for like a split second and it feels like that throughout my drive. It's weird.
#7
My mistake, on a 1995/1996 Ranger the 4x4 module is between GEM and firewall, so behind it in terms of looking in the radio cavity
Description here:
" It's more of a cube, maybe 3 inches on a side. As he recalls, the GEM was mounted just to the left of the radio location, and the 4WD control module was at the same height and within about 6 or 8 inches of the GEM. It only has a few wires running to it.
Description here:
" It's more of a cube, maybe 3 inches on a side. As he recalls, the GEM was mounted just to the left of the radio location, and the 4WD control module was at the same height and within about 6 or 8 inches of the GEM. It only has a few wires running to it.
#8
ive verified that all my connections are secure to the 4x4 module, I've replaced the 4x4 module, all fuses are good. All relays are good, disconnecting the battery for 5 minutes didn't work either. I still hear the same ickint noise coming from the 4x4 module relay even after installing a new one. Lights still flash.
Any other ideas??
Any other ideas??
#10
No it doesn't change anything.
I feel like the issue has to do with the 4x4 shift module, I can hear it clicking upon startup, same thing even after I replaced it. But if I remove the module completely and start up, no 4wd lights flash. I haven't gotten around to checking continuity or resistance between the gem Module and the 4x4 module yet, I plan to do that sometime today. It's just weird that everything else that is connected to the gem Module is working just fine.
I did read some posts about there being an LED indicator and a test button on a 4x4 module. But can't seem to find out where this could be at? I'd like to test my gem Module to but don't know how to go about it. Any info about this would be helpful as well.
I feel like the issue has to do with the 4x4 shift module, I can hear it clicking upon startup, same thing even after I replaced it. But if I remove the module completely and start up, no 4wd lights flash. I haven't gotten around to checking continuity or resistance between the gem Module and the 4x4 module yet, I plan to do that sometime today. It's just weird that everything else that is connected to the gem Module is working just fine.
I did read some posts about there being an LED indicator and a test button on a 4x4 module. But can't seem to find out where this could be at? I'd like to test my gem Module to but don't know how to go about it. Any info about this would be helpful as well.
#12
#13
There is no way to test a GEM module
Yes you can use a 1995-1997 GEM from a wrecking yard, needs to be from 4x4 of course, and should match your options, i.e. power windows and door locks if so equipped
Engine size doesn't matter, GEM just deals with Body Electrics
Mazda B-series 1995 to 1997 would also work
I would check the connector on the shift motor if you haven't, when you turn on the key the GEM checks position of shift motor, if it can't "see" it because of bad or corroded connections it will flash dash lights.
So make sure wires on both sides of connector are OK and pins in the connector look good
Yes you can use a 1995-1997 GEM from a wrecking yard, needs to be from 4x4 of course, and should match your options, i.e. power windows and door locks if so equipped
Engine size doesn't matter, GEM just deals with Body Electrics
Mazda B-series 1995 to 1997 would also work
I would check the connector on the shift motor if you haven't, when you turn on the key the GEM checks position of shift motor, if it can't "see" it because of bad or corroded connections it will flash dash lights.
So make sure wires on both sides of connector are OK and pins in the connector look good
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