After two winters of ownership, I have come to realize that there is a Wrangler windshield defroster issue. A quick search on the internet reveals that both Wrangler JK and JL owners seem to be experiencing the same issue, as is evident in online forums. The problem is illustrated below and in this video. Among the various options for mods to address this issue, the results from my mod are also shown below.
An Illustration of the Wrangler Windshield Defroster Issue
The image below is a simulated image of the problem I was experiencing, as I installed my mod prior to thinking of taking a picture. Essentially, the defroster would only defrost the centre of the windshield and ice would build up towards the edges while driving.
Experiencing this defrost pattern in my Jeep Wrangler JL was surprising, given that the defrost vents at the bottom of the windshield extend from the lower driver’s side corner to the lower passenger side.
Thus, even with the existence of the defrost vent holes, a defrost heat pattern illustrated below appears to be what is happening to explain this Jeep Wrangler windshield defrost issue.
Online Evidence of the Wrangler Windshield Defrost Issue
A careful online search of “Wrangler Windshield Defrost Issue” reveals a multitude of posts in many Forums addressing this issue.
A careful read through the posts will offer a number Jeep Wrangler owners solutions or hacks for solving this issue. It was after careful review and consideration that I chose my solution
My Windshield Defroster Hack
Although the forum has many suggestions to pick from, I chose to cover the central vents with a piece of flat aluminum bar ⅛” thick by 1” wide by 19” long. I drilled holes about every 2”, and then spray painted it with satin black wood stove paint. The bar would be held in place with toggle bolts. A short or shallow handled screwdriver was needed due to the windshield being present. These bolts had to be cut a couple inches short to be able to fit into the vent without obstruction, and are tricky to use. Zip ties would also suffice.
The intent of this design was to have a baffle of sorts that would permit some heat up the centre through the holes, but direct more heat towards the side vents, as illustrated below.
Initial defroster baffle results were promising as they showed successful diversion of flow towards the sides of the windshield. Defrosting of the outer edges is a big deal, as dangerous build up of ice would occur in this area.
The whole windshield eventually thawed, but there is still a desire to have the whole windshield defrost at the same rate. The areas in front of the passenger and driver did not defrost as quickly as the centre and outer edges. The intent will be to shorten the baffle by a few inches and test again.
The Jeep Wrangler windshield defrost issue is something many Jeep Wrangler JK and JL owners are experiencing, as noted in many online forums. Many different DIY hacks have been successfully implemented, as mentioned in said forums. However, one recent post mentioned that a defroster related part behind the dash was discovered to be either not-connected or constricted, and was repaired under warranty. So if you still have warranty left, you may want to investigate this solution before attempting a diy hack.