Update 16 March 2023:
First of all I'm still offering this service to anyone interested, but since I've lately helped several troubleshoot window issues that weren't connected to the relay assembly, I wanted to offer somewhat of a troubleshooting guide so that anyone wanting their relay box refurbished can run through it first and be absolutely sure they need (or just want) to have their unit refurbished. I HATE spending money on something thinking it'll fix an issue and then realizing after the fact that it wasn't the cause. In some cases it ends up being money wasted, so I try to help others avoid that aggravation. Now given the age of these units and some of the environments our Cruisers are in, I'll still recommend a refurb; however there ARE other potential causes to power window problems.
As an overview, if your other windows and power locks are working but your driver's window is not, odds are very good your relay assembly is the culprit. If everything works but the auto-down function of your driver's window doesn't work, this is also very likely due to a fault in the relay assembly. If NOTHING works, or everything is just operating weak/slow, there are several things to consider. I'll go through them as best I can, adding more info as time goes on.
Potential cause #1: Thermal breaker. On the fuse panel, to the right there are two round silver components. These are thermal breakers. The top one is for the HVAC (AC, front and rear blowers) and the bottom is for the power windows and the power locks. If neither your windows nor your locks are working, check this. They can be reset by inserting a pin or paperclip into the small hole and listening for a faint click. If it WAS popped, you now have two things to consider. The first is that something caused it to pop in the first place and now needs to be found to avoid it popping again, and the second is that thermal breakers are more prone to popping after the first time they go, so you'll want to replace it once you find and solve the issue. Last time I ordered one, they were about $35 a piece.
Potential cause #2: The master switch assembly. These have long been notorious for failure due to carbon buildup on the switch contacts. In all honesty, I feel this is one of the very rare situations where Toyota's design and materials were sub par. The switch contacts inside suffer from rapid buildup of carbon deposits due to electrical arcing and are not a hard enough material to better resist the pitting that occurs with long term use. Fortunately there are still OEM replacements available, along with good quality (though not available in gray) aftermarket units made by Switch Doctor. I have a Switch Doctor unit myself and it works very well. I haven't taken it apart since installation yet though to see how the wear compares to an OEM unit. If your windows are painfully slow and your door locks weak or non responsive, the master switch is usually one of many causes.
Potential cause #3: Damaged/corroded wiring, splices and connectors. Here is where we get into the "how deep do you want to dive into this?" portion of window and door lock issues. The first two items I covered are the simplest things to check and repair (or replace). This portion involves having knowledge of the FJ62 wiring layout and ability to chase wire runs. Knowledge & experience are highly recommended with this, and I will say the body & electrical FSM is absolutely mandatory. Essentially this will involve closely inspecting the wiring in each door and conducting any repairs necessary (just focus on one door at a time. Don't overwhelm yourself). I'll be getting more in depth with this process in the near future.
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After doing this on my own rig with success, I commented in @slcfj62's thread here (FJ62 Drivers Power Window (AutoDown) Relay Fix - https://forum.ih8mud.com/threads/fj62-drivers-power-window-autodown-relay-fix.362868/) about considering offering a service of refurbishing these assemblies for anyone who either doesn't have the time/resources or the soldering skills to attempt this. After @4Cruisers was gracious enough to be my first customer, I've documented the refurb process on his relay box so that I can detail the work I do to refurbish these boxes and give the user a "near new" OEM quality part at a fraction of the cost of 30+ year old used parts. 4Cruisers's part was in much better beginning condition than my own, so this was a great part to get details of the process. As received, he reported that his driver's window would no longer go down. This made for a perfect opportunity to repair and renew a damaged product.
The part as I received it. Considering its age, very clean and no corrosion that I could see on the mounting brackets. To be expected in either a dry climate or if the vapor barriers were never removed from the doors (mine were years ago and my own mounting brackets have some surface rust).
The assembly immediately after dismantling. The plastic box is made of ABS. While working this one I was able to figure out a way to remove the "cap" while minimizing risk of damaging the plastic. Though only a couple of the tabs on his required repair, my own didn't fare so well; but I keep a supply of ABS solvent cement that makes for a perfect repair of ABS plastic. Rather than being a simple adhesive, it chemically fuses the plastic together. The cure time is three days for full strength, but the repair is just as strong as new plastic. With this I'm able to repair any breaks or cracks in ABS as long as there are not MISSING parts. 4Cruisers's and my own part repaired beautifully with using an insulin syringe as an applicator to avoid mess.
The backside of an as yet untouched PCB. These circuits are very simple. Though I didn't make it as far as the circuit analysis class in my electronics engineering course (divorce at the time and wasn't about to put myself in a position where my GI Bill could possibly be usurped from me), I'm confident that if I sit down and take the time to pore over the specs of each component and trace the current paths, it wouldn't take me long to break it down.
First of all I'm still offering this service to anyone interested, but since I've lately helped several troubleshoot window issues that weren't connected to the relay assembly, I wanted to offer somewhat of a troubleshooting guide so that anyone wanting their relay box refurbished can run through it first and be absolutely sure they need (or just want) to have their unit refurbished. I HATE spending money on something thinking it'll fix an issue and then realizing after the fact that it wasn't the cause. In some cases it ends up being money wasted, so I try to help others avoid that aggravation. Now given the age of these units and some of the environments our Cruisers are in, I'll still recommend a refurb; however there ARE other potential causes to power window problems.
As an overview, if your other windows and power locks are working but your driver's window is not, odds are very good your relay assembly is the culprit. If everything works but the auto-down function of your driver's window doesn't work, this is also very likely due to a fault in the relay assembly. If NOTHING works, or everything is just operating weak/slow, there are several things to consider. I'll go through them as best I can, adding more info as time goes on.
Potential cause #1: Thermal breaker. On the fuse panel, to the right there are two round silver components. These are thermal breakers. The top one is for the HVAC (AC, front and rear blowers) and the bottom is for the power windows and the power locks. If neither your windows nor your locks are working, check this. They can be reset by inserting a pin or paperclip into the small hole and listening for a faint click. If it WAS popped, you now have two things to consider. The first is that something caused it to pop in the first place and now needs to be found to avoid it popping again, and the second is that thermal breakers are more prone to popping after the first time they go, so you'll want to replace it once you find and solve the issue. Last time I ordered one, they were about $35 a piece.
Potential cause #2: The master switch assembly. These have long been notorious for failure due to carbon buildup on the switch contacts. In all honesty, I feel this is one of the very rare situations where Toyota's design and materials were sub par. The switch contacts inside suffer from rapid buildup of carbon deposits due to electrical arcing and are not a hard enough material to better resist the pitting that occurs with long term use. Fortunately there are still OEM replacements available, along with good quality (though not available in gray) aftermarket units made by Switch Doctor. I have a Switch Doctor unit myself and it works very well. I haven't taken it apart since installation yet though to see how the wear compares to an OEM unit. If your windows are painfully slow and your door locks weak or non responsive, the master switch is usually one of many causes.
Potential cause #3: Damaged/corroded wiring, splices and connectors. Here is where we get into the "how deep do you want to dive into this?" portion of window and door lock issues. The first two items I covered are the simplest things to check and repair (or replace). This portion involves having knowledge of the FJ62 wiring layout and ability to chase wire runs. Knowledge & experience are highly recommended with this, and I will say the body & electrical FSM is absolutely mandatory. Essentially this will involve closely inspecting the wiring in each door and conducting any repairs necessary (just focus on one door at a time. Don't overwhelm yourself). I'll be getting more in depth with this process in the near future.
-----------------------------------------------------------------------------------------------------------------------------
After doing this on my own rig with success, I commented in @slcfj62's thread here (FJ62 Drivers Power Window (AutoDown) Relay Fix - https://forum.ih8mud.com/threads/fj62-drivers-power-window-autodown-relay-fix.362868/) about considering offering a service of refurbishing these assemblies for anyone who either doesn't have the time/resources or the soldering skills to attempt this. After @4Cruisers was gracious enough to be my first customer, I've documented the refurb process on his relay box so that I can detail the work I do to refurbish these boxes and give the user a "near new" OEM quality part at a fraction of the cost of 30+ year old used parts. 4Cruisers's part was in much better beginning condition than my own, so this was a great part to get details of the process. As received, he reported that his driver's window would no longer go down. This made for a perfect opportunity to repair and renew a damaged product.
The part as I received it. Considering its age, very clean and no corrosion that I could see on the mounting brackets. To be expected in either a dry climate or if the vapor barriers were never removed from the doors (mine were years ago and my own mounting brackets have some surface rust).
The assembly immediately after dismantling. The plastic box is made of ABS. While working this one I was able to figure out a way to remove the "cap" while minimizing risk of damaging the plastic. Though only a couple of the tabs on his required repair, my own didn't fare so well; but I keep a supply of ABS solvent cement that makes for a perfect repair of ABS plastic. Rather than being a simple adhesive, it chemically fuses the plastic together. The cure time is three days for full strength, but the repair is just as strong as new plastic. With this I'm able to repair any breaks or cracks in ABS as long as there are not MISSING parts. 4Cruisers's and my own part repaired beautifully with using an insulin syringe as an applicator to avoid mess.
The backside of an as yet untouched PCB. These circuits are very simple. Though I didn't make it as far as the circuit analysis class in my electronics engineering course (divorce at the time and wasn't about to put myself in a position where my GI Bill could possibly be usurped from me), I'm confident that if I sit down and take the time to pore over the specs of each component and trace the current paths, it wouldn't take me long to break it down.
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