electrical problems after it rains

[LightlyToasted]

Originally Posted by ard

I am idly wondering if a short/issue at some bus connector somewhere can be triggering the odd collection of faults- so it might not be AT the specific module itself, but the fault at a distant connector causing spurious faults elsewhere? Just WAGing...

I strongly suspect a CAN bus module is failing somewhere. Sometimes my code scanner cannot connect via the OBD port.

[LightlyToasted]

Got around to wet testing today. All 4 sunroof drains were clear.

When testing the rear tail gate, water was getting around the left side wiring boot between the body and tail gate, at the body opening. The boots seemed to be in very good condition, but just don't seem to seal properly at the top of the opening in the body.

Water was entering the left rear, and soaking the fabric lining, especially at the bottom. Lots of modules were wet. A heavy rain would have flooded that compartment.

I put a bead of silicone around each opening to seal the boots to the body and tail gate, including an extra exterior bead at the top of the body seals. This silicone goes on white so it's easy to clean up excess, and dries clear.

Subsequent wet test passed. Hope no electronics were fried. I was able to pull up and clear fault codes, and so far they haven't returned.

[ard]

Well, wont win any concours... but kudos for finsing the issue and posting!

Did you dry out all the modules and resolve all the other issues?? If so, excellent- lucky you got it before something fried

[LightlyToasted]

Originally Posted by ard

Did you dry out all the modules and resolve all the other issues?? If so, excellent- lucky you got it before something fried

By the time I got around to checking things out, the modules had already dried out. It rained hard last night and the vehicle was outside. No leaks and no problems! So far so good.

New grommets aren't very expensive, but I suspect it would be a challenge to fish the wires through into the tailgate, so I'm not going to bother so long as the silicone holds.

[seattle]

yesterday, found water (again) in passenger side rear compartment. A month or more ago, tailgate module fried because of water there. At that time, I thought water got in there through side vents after pressure washing.

I was occasionally checking that area over coming weeks and things stayed dry. Yesterday, after a week of heavy rains (Seattle), checked again - water!

Luckily, I got to it while it was still raining and I observed water dripping from somewhere above. Traced it to the wiring boot.

Applied generous amount of silicone and reassembled.

It is a bad design, really. The opening for the wire on the body should have elevated edges. That alone would have prevented most water without any special seal. Instead, it is flat (see OP's pics) and we have to rely on rubber to stop the water. That doesn't quite work.

Also, observed little plastic flap of the sunroof drain (right next to the wiring boot) was pushed in too deep into the tube and not opening properly. Took it out, cleaned and pushed it in properly - now opens easily. That had a risk of flooding from sunroof.

[heatmizr]

Are those pics from the UPPER tailgate wiring? near the upper tailgate hinge?
or lower...

[seattle]

Upper

[Dieseldonkey]

Originally Posted by seattle

yesterday, found water (again) in passenger side rear compartment. A month or more ago, tailgate module fried because of water there. At that time, I thought water got in there through side vents after pressure washing.

I was occasionally checking that area over coming weeks and things stayed dry. Yesterday, after a week of heavy rains (Seattle), checked again - water!

Luckily, I got to it while it was still raining and I observed water dripping from somewhere above. Traced it to the wiring boot.

Applied generous amount of silicone and reassembled.

It is a bad design, really. The opening for the wire on the body should have elevated edges. That alone would have prevented most water without any special seal. Instead, it is flat (see OP's pics) and we have to rely on rubber to stop the water. That doesn't quite work.

Also, observed little plastic flap of the sunroof drain (right next to the wiring boot) was pushed in too deep into the tube and not opening properly. Took it out, cleaned and pushed it in properly - now opens easily. That had a risk of flooding from sunroof.

Same deal here a year ago. Fried my Tailgate lift module!
Ordered a used one on eBay and it came fried. Must be a common problem.
Round 3 I siliconed both boots like above where they enter the body and still get occasional water in right rear compartment.
Perhaps the boot is damaged and needs more silicone.
Great thread as I'm still hunting down the water intrusion!

[richievn]

I got into similar situation last weekend after 2 hours of heavy rain. Dont know what happened but I had a pool of water on the passenger side rear compartment with load of its underneath the battery tray. The fabric was wet from the compartment to the trunk floor arear.

I already soaked out the water but couldnt find the actual reason. Possibly sunroof but also the plasttric trim next to the taillight. Icould see it cracking and leaves a gap there but Im not sure. Any body has the part number for those 2 plastic pieces?i looked up on realoem but couldnt find

[ard]

have you tested the drains on the sunroof? make sure they actually drain?


Seems better than replacing parts that might not be the issue...at least easier to test