***Solved*** No power windows / dome lights / wipers / rear defrost

[usapadyra]

So, sadly, I have to carry on with this.

The problem returned after a long time (2 weeks) sitting in the rain that came over NorCal. The issue also first occurred sitting parked in the rain, and resolved after going for a drive in the dry.

This time, again, the issue resolved entirely after about an hour of driving in dry weather. But I did do some much more thorough testing of devices this time when the issue was present.

The full list of issues is as follows. These either all happen at the same time or everything is fine. None of these happen independently of each other.

- no dome lights front or rear
- no windshield wipers or washer pump
- no rear defrost
- no power windows
- no bong when headlights are on with ignition off and drivers door open

I'm thinking is it possible that the GEM is to blame?

At first I thought it might be broken wires in the drivers door jamb, but can things like windshield wipers and rear defrost be effected by broken wires there?

I did recently change:
- accessory delay relay
- battery saver relay

No help.

Cheers,
Toby

 

[drdoom]

Toby mine is not resolved yet either. Wet days, periods of non use seem to make it fault. Dry days no problem.

 

[Turdle]

Gonna have to dig into the door jam wiring, don't avoid it like you have been

 

[drdoom]

Gonna have to dig into the door jam wiring, don't avoid it like you have been

So that affects the 4x4 system how?

 

[Turdle]

So that affects the 4x4 system how?

I was answering op. Your problem is different. Might need a new thread.

 

[usapadyra]

I was answering op. Your problem is different. Might need a new thread.

So since leaving Grass Valley / Tahoe (rain / snow constantly) and driving hundreds of miles through the dry desert of Nevada it has pretty much cleared up.

I understand how it could affect the power windows and dome lights. But how does the wiring through the driver door affect wipers / washer motor or the rear defrost? Don't want to be presumptuous, these things are always more complicated than laymen like me like to think they are, I just want to understand how that would be possible.

 

[drdoom]

So since leaving Grass Valley / Tahoe (rain / snow constantly) and driving hundreds of miles through the dry desert of Nevada it has pretty much cleared up.

I understand how it could affect the power windows and dome lights. But how does the wiring through the driver door affect wipers / washer motor or the rear defrost? Don't want to be presumptuous, these things are always more complicated than laymen like me like to think they are, I just want to understand how that would be possible.

Wipers are going out on mine too.
And I apologize for hitchhiking the thread here, I'll try to keep relevant.
My partial list again:
Dome lights
Wipers
Under hood light
Power Windows (locks work IIRC)
4X4

When it faults again I'll get a better list.
Like I should check the radio too.
I don't remember what year you have but a long time ago I had a window fault, and first thing I did was take the bolt out of the door jamb connector. So I could check for bad wires, I didn't find any with a quick visual. Bolted the connector back together and everything was good...bad contact.

 

[usapadyra]

After all this time, I actually have an update on this that may be useful to others with the same issue.

I took a long road trip through the South Western states from April to May 2023. The weather during the trip was exclusively dry and hot. I had zero issues with electronics. Everything worked as it should. From May until October, my car was stored on a friend's property in Northern California. The car was out in the open and undriven all the while. Again, apart from the odd rainy day, it would have been dry and hot the entire time.

When I returned to my truck, everything was still working as it should, and continued to do so for the couple of weeks until the rain started.

Almost like clockwork, after a couple of days of wet weather, the problem returned. No wipers, no rear defrost, no windows and no interior lights.

Previously I had thought that the issue might have been caused by water ingress, however, this time my car had been parked under a roofed car port and absolutely no water had been falling on the car. It was definitely an effect of the humidity itself. Even in the continued wet weather, the functions would return if I took a long drive with the AC pushing dry air into the car.

I decided to get behind the dash and take the GEM out. Figuring I might see the problem (loose connection or burn marks on the circuit board) and if not, I would at least have the serial number to seek out a replacement part.

No connections were loose. I took the circuit board out of the plastic housing and visually it looked normal.

As a last resort before spending $100 on a used part, I bought a can of WD-40 contact cleaner.

Holding the circuit board vertically, I sprayed the cleaner down at a 45-degree angle to the board. Perhaps only a centimeter from the board. Starting at the top and working my way down.

I did this on both sides. Allowing it to dry between blasts. Ended up using the whole can.

Left it to dry overnight and upon reinstalling it now works without issue!

I have since come up to Tahoe where it's raining and snowing a little and the problem has not returned.


TLDR: if you are having a similar issue as outlined in this thread, it might be worth giving the GEM a good spray down with electrical parts / contact cleaner before looking for and spending on a replacement. A can is about $10. There are plenty of brands. I believe the key ingredient is heptane, which evaporates readily and does not leave a residue. You could probably use MAF sensor cleaner as well. Just don't use brake cleaner or carb cleaner.


For anyone who might be interested, I have an idea as to what was going on:

I work seasonally during the fall and winter, which involves camping in the car. I also have a bad habit of vaping. In the wet weather, I have no choice but to leave the windows all rolled up while I sleep. Before going to sleep, and usually in the morning, I would spend a good while puffing away on the vape, leading to the car being pretty much filled with the vapor. It does leave a residue on the inside of the windows, and every now and again I would have to clean this off.

I believe that the residue was not only forming on the windows but also on the GEM circuit board. There is a big gap in the left side of the console containing the radio and such, near the driver's right knee, where air from the cab can flow through. The GEM is right above this gap. For anyone who doesn't know, one of the primary ingredients in vape fluid is propylene glycol, which is hygroscopic.

This is just a theory, mind, but I believe the residue from my vaping was settling on the circuit board. When dry, this residue was probably not conductive enough by itself to cause any issues. However, it could be that the residue was absorbing moisture during humid weather, and this was enough to interfere with the proper functioning of the GEM.

Assuming that the GEM is where the car gets all of its 'timing' from, I have to guess that it is this functionality failing or shorting or something that caused the related issues:

- Wipers rely on timing depending on the intermittent speed they are set to

- The rear defrost has a timer to turn itself off

- The interior lights and power windows are affected by the battery saver and / or accessory delay function


Pretty happy that I fixed this. Hopefully it's cured for the long term. It was frustrating thinking I might have to lose the car over something so simple as non-functioning wipers!

 

[swak6287]

After all this time, I actually have an update on this that may be useful to others with the same issue.

I took a long road trip through the South Western states from April to May 2023. The weather during the trip was exclusively dry and hot. I had zero issues with electronics. Everything worked as it should. From May until October, my car was stored on a friend's property in Northern California. The car was out in the open and undriven all the while. Again, apart from the odd rainy day, it would have been dry and hot the entire time.

When I returned to my truck, everything was still working as it should, and continued to do so for the couple of weeks until the rain started.

Almost like clockwork, after a couple of days of wet weather, the problem returned. No wipers, no rear defrost, no windows and no interior lights.

Previously I had thought that the issue might have been caused by water ingress, however, this time my car had been parked under a roofed car port and absolutely no water had been falling on the car. It was definitely an effect of the humidity itself. Even in the continued wet weather, the functions would return if I took a long drive with the AC pushing dry air into the car.

I decided to get behind the dash and take the GEM out. Figuring I might see the problem (loose connection or burn marks on the circuit board) and if not, I would at least have the serial number to seek out a replacement part.

No connections were loose. I took the circuit board out of the plastic housing and visually it looked normal.

As a last resort before spending $100 on a used part, I bought a can of WD-40 contact cleaner.

Holding the circuit board vertically, I sprayed the cleaner down at a 45-degree angle to the board. Perhaps only a centimeter from the board. Starting at the top and working my way down.

I did this on both sides. Allowing it to dry between blasts. Ended up using the whole can.

Left it to dry overnight and upon reinstalling it now works without issue!

I have since come up to Tahoe where it's raining and snowing a little and the problem has not returned.


TLDR: if you are having a similar issue as outlined in this thread, it might be worth giving the GEM a good spray down with electrical parts / contact cleaner before looking for and spending on a replacement. A can is about $10. There are plenty of brands. I believe the key ingredient is heptane, which evaporates readily and does not leave a residue. You could probably use MAF sensor cleaner as well. Just don't use brake cleaner or carb cleaner.


For anyone who might be interested, I have an idea as to what was going on:

I work seasonally during the fall and winter, which involves camping in the car. I also have a bad habit of vaping. In the wet weather, I have no choice but to leave the windows all rolled up while I sleep. Before going to sleep, and usually in the morning, I would spend a good while puffing away on the vape, leading to the car being pretty much filled with the vapor. It does leave a residue on the inside of the windows, and every now and again I would have to clean this off.

I believe that the residue was not only forming on the windows but also on the GEM circuit board. There is a big gap in the left side of the console containing the radio and such, near the driver's right knee, where air from the cab can flow through. The GEM is right above this gap. For anyone who doesn't know, one of the primary ingredients in vape fluid is propylene glycol, which is hygroscopic.

This is just a theory, mind, but I believe the residue from my vaping was settling on the circuit board. When dry, this residue was probably not conductive enough by itself to cause any issues. However, it could be that the residue was absorbing moisture during humid weather, and this was enough to interfere with the proper functioning of the GEM.

Assuming that the GEM is where the car gets all of its 'timing' from, I have to guess that it is this functionality failing or shorting or something that caused the related issues:

- Wipers rely on timing depending on the intermittent speed they are set to

- The rear defrost has a timer to turn itself off

- The interior lights and power windows are affected by the battery saver and / or accessory delay function


Pretty happy that I fixed this. Hopefully it's cured for the long term. It was frustrating thinking I might have to lose the car over something so simple as non-functioning wipers!

usapadyra, I just bought a new to me 97 with this same problem, no wiper and no interior lights. I checked all my fuses yesterday, and they all looked ok. I will pull the radio out and check the GEM back there and report back. I hope this is an easy fix, like yours.

 

[usapadyra]

usapadyra, I just bought a new to me 97 with this same problem, no wiper and no interior lights. I checked all my fuses yesterday, and they all looked ok. I will pull the radio out and check the GEM back there and report back. I hope this is an easy fix, like yours.

Hopefully!

I haven't had a single issue since I did this. Despite plenty of snow, rain and general damp weather.

How are your power windows and rear defrost?

 

[swak6287]

Hopefully!

I haven't had a single issue since I did this. Despite plenty of snow, rain and general damp weather.

How are your power windows and rear defrost?

Power window works. rear defrost, had not used it since I bought it last week.