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So, I have a working tailgate glass popper that opens completely at the touch of a button on the key fob or dash button.
How?
There is a beer can sized solenoid in the tailgate that yanks on a length of wire rope that is tethered to the glass release mechanism. First, if your tailgate popper hasn't worked in a few years, then the solenoid is most likely jammed. The slug in the center of the solenoid is a big lump of highly ferritic steel or even straight iron, it has to be, because science. In other words it is super prone to rust so it will need to be un-stuck.
The second thing that goes wrong, is over time the various electrical connections for the solenoid energizer wire and ground go high resistance. This happens due to time and corrosion, but you really need as many volts going to the solenoid as possible because she's a power hungry whore of a thing.
Thirdly, the solenoid does not have enough grunt to actually trigger the release mechanism. So you instead want to rely on the weight of the slug in the solenoid to 'jerk' the release mechanism like a slide hammer.
Fourthly! The gas struts are effectively 'over centered' when the glass is shut (ask your dad what this means). So you will need to rely on the compression of the glass seal to actually push the glass open the first 1/2" before the struts can actually take over and do the rest. Correctly adjusting the tailgate also helps reduce that annoying ‘Typhoon squeek’ when you roll down the road, so this is a must do!
To fix the damn thing. Follow these steps:
Step 1.
Stuck Solenoid.
- Open the tailgate and remove the big plastic inner cover
- Remove the plastic film vapor shield.
- Remove the silver, steel bracket in the center of the tailgate (2 x silver 7mm head screws) and the black sheetmetal cover (4 x black 10mm head screws)
- Unbolt the solenoid(2 x silver 10mm head screws), then you will be able to remove it through the hole that the center bracket opened up.
The center pin of the solenoid should float in and out very freely by hand. If it is tight at all, then squirt some anti cease in through the hole around the pin and manually cycle it until it frees up completely. If you cannot get it to mover freely, then you'll need a new one!
Step 2.
Electrimatronics
- Now that you've access to the solenoid, pull off the connector on the end and clean both contacts with contact cleaner if needed, sometimes just taking it on and off a few times will scuff up the copper and get it going nicely again.
- There is an earth strap from the tailgate to the body down by the left hand hinge. Remove both ends of the strap, scuff up the terminals with fine sandpaper and re-install.
- Find the rubber conduit between the bottom of the tailgate and the body (immediately behind the rear bumper, access from underneath). Remove the body end of the conduit by pulling on it carefully. There is a wire connector just other side the hole in the body, this can be pulled through the hole and disconnected. Again clean both contacts then re-connect the connector and re-install the conduit.
-Take off the fuse-box cover immediately above and to the left of the brake pedal.
- Identify the tailgate popper relay. It is hanging freely in front of the fuse panel on a three wire base (orange, brown and black). It is white on my truck and it is the one that goes 'click' when you push the key fob tailgate button or the button on the dash. If it does not go click, then you need a new one, or the fuse has blown!
- Remove the tailgate relay by holding open the two locking tabs either side of the relay and pulling it out. Again check and clean the three contacts and at this point if you've a multi-meter you can probe the three wires. (thick black wire goes to the solenoid, orange is ground through the transmission Park interlock and brown comes from the dash button).*
Step 3.
Limp-wristed Solenoid.
- When re-fastening the solenoid into the tailgate after cleaning, arm the latch manually as if you had just closed the tailgate glass.
- The wire rope from the solenoid to the latch mechanism should be left with as much slack as the solenoid mounting holes can provide.
- Now when the solenoid fires, the core will pick up speed as it takes up the slack in the wire rope. When it reaches the end of the slack, the hammering effect will be enough to trigger the latch mechanism.
- Free up the moving parts of the latch mechanism with penetrating lube and apply grease, this will help a lot.
Step 4.
Pop that booty.
- Locate the tailgate latch posts, these are the large steel striker posts that the lower tailgate latches onto either side of the rear hatch opening.
- The end of the latch posts have a large 6 point ‘Torx’ socket. Use a torx bit or key to loosen the posts and you will be able to move them in or out about 1/8”.
- This will take trial and error, but you want to re-position both latch posts so that when the tailgate is closed the body line between the gate and the paintwork above the tail lights is flush when closed.
- Once the tailgate is adjusted you should end up with much better seal compression on the rear window, this should help achieve a good POP when you need it AND reduce rear glass jiggle when you’re driving.
- If the rear glass still doesn’t pop, you may need new gas struts.**
*The dash mounted release button is actually the source of a lot of resistance between the battery and the tailgate solenoid. This is because GM in the 90’s did not understand that switching relays are needed whenever a power hungry solenoid is present (I give you the ‘purple wire’ click-click starter dilemma). I would suggest that you pick up a 4 pin 32A relay from the local parts store and replace the factory 3 pin relay. The 4 pin relay can then be activated by the dash button but you can send power DIRECTLY from the battery / fuse panel bus straight to the solenoid for uninterrupted juice. Hell, buy two because you'll probably need one for your starter solenoid too!
**If you’re still struggling to get a nice pop, perhaps pick up some self adhesive sealing foam from the hardware store, this stuff is designed to be a draft stopper in household doors, but if you stick a small patch of it just above the window latch, it could provide that initial POP that you need to release the window completely.
How?
There is a beer can sized solenoid in the tailgate that yanks on a length of wire rope that is tethered to the glass release mechanism. First, if your tailgate popper hasn't worked in a few years, then the solenoid is most likely jammed. The slug in the center of the solenoid is a big lump of highly ferritic steel or even straight iron, it has to be, because science. In other words it is super prone to rust so it will need to be un-stuck.
The second thing that goes wrong, is over time the various electrical connections for the solenoid energizer wire and ground go high resistance. This happens due to time and corrosion, but you really need as many volts going to the solenoid as possible because she's a power hungry whore of a thing.
Thirdly, the solenoid does not have enough grunt to actually trigger the release mechanism. So you instead want to rely on the weight of the slug in the solenoid to 'jerk' the release mechanism like a slide hammer.
Fourthly! The gas struts are effectively 'over centered' when the glass is shut (ask your dad what this means). So you will need to rely on the compression of the glass seal to actually push the glass open the first 1/2" before the struts can actually take over and do the rest. Correctly adjusting the tailgate also helps reduce that annoying ‘Typhoon squeek’ when you roll down the road, so this is a must do!
To fix the damn thing. Follow these steps:
Step 1.
Stuck Solenoid.
- Open the tailgate and remove the big plastic inner cover
- Remove the plastic film vapor shield.
- Remove the silver, steel bracket in the center of the tailgate (2 x silver 7mm head screws) and the black sheetmetal cover (4 x black 10mm head screws)
- Unbolt the solenoid(2 x silver 10mm head screws), then you will be able to remove it through the hole that the center bracket opened up.
The center pin of the solenoid should float in and out very freely by hand. If it is tight at all, then squirt some anti cease in through the hole around the pin and manually cycle it until it frees up completely. If you cannot get it to mover freely, then you'll need a new one!
Step 2.
Electrimatronics
- Now that you've access to the solenoid, pull off the connector on the end and clean both contacts with contact cleaner if needed, sometimes just taking it on and off a few times will scuff up the copper and get it going nicely again.
- There is an earth strap from the tailgate to the body down by the left hand hinge. Remove both ends of the strap, scuff up the terminals with fine sandpaper and re-install.
- Find the rubber conduit between the bottom of the tailgate and the body (immediately behind the rear bumper, access from underneath). Remove the body end of the conduit by pulling on it carefully. There is a wire connector just other side the hole in the body, this can be pulled through the hole and disconnected. Again clean both contacts then re-connect the connector and re-install the conduit.
-Take off the fuse-box cover immediately above and to the left of the brake pedal.
- Identify the tailgate popper relay. It is hanging freely in front of the fuse panel on a three wire base (orange, brown and black). It is white on my truck and it is the one that goes 'click' when you push the key fob tailgate button or the button on the dash. If it does not go click, then you need a new one, or the fuse has blown!
- Remove the tailgate relay by holding open the two locking tabs either side of the relay and pulling it out. Again check and clean the three contacts and at this point if you've a multi-meter you can probe the three wires. (thick black wire goes to the solenoid, orange is ground through the transmission Park interlock and brown comes from the dash button).*
Step 3.
Limp-wristed Solenoid.
- When re-fastening the solenoid into the tailgate after cleaning, arm the latch manually as if you had just closed the tailgate glass.
- The wire rope from the solenoid to the latch mechanism should be left with as much slack as the solenoid mounting holes can provide.
- Now when the solenoid fires, the core will pick up speed as it takes up the slack in the wire rope. When it reaches the end of the slack, the hammering effect will be enough to trigger the latch mechanism.
- Free up the moving parts of the latch mechanism with penetrating lube and apply grease, this will help a lot.
Step 4.
Pop that booty.
- Locate the tailgate latch posts, these are the large steel striker posts that the lower tailgate latches onto either side of the rear hatch opening.
- The end of the latch posts have a large 6 point ‘Torx’ socket. Use a torx bit or key to loosen the posts and you will be able to move them in or out about 1/8”.
- This will take trial and error, but you want to re-position both latch posts so that when the tailgate is closed the body line between the gate and the paintwork above the tail lights is flush when closed.
- Once the tailgate is adjusted you should end up with much better seal compression on the rear window, this should help achieve a good POP when you need it AND reduce rear glass jiggle when you’re driving.
- If the rear glass still doesn’t pop, you may need new gas struts.**
*The dash mounted release button is actually the source of a lot of resistance between the battery and the tailgate solenoid. This is because GM in the 90’s did not understand that switching relays are needed whenever a power hungry solenoid is present (I give you the ‘purple wire’ click-click starter dilemma). I would suggest that you pick up a 4 pin 32A relay from the local parts store and replace the factory 3 pin relay. The 4 pin relay can then be activated by the dash button but you can send power DIRECTLY from the battery / fuse panel bus straight to the solenoid for uninterrupted juice. Hell, buy two because you'll probably need one for your starter solenoid too!
**If you’re still struggling to get a nice pop, perhaps pick up some self adhesive sealing foam from the hardware store, this stuff is designed to be a draft stopper in household doors, but if you stick a small patch of it just above the window latch, it could provide that initial POP that you need to release the window completely.
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