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2021 Models with Trailer Light Check

RamGuy84

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Anyone with this have a pic of the gauge cluster screen or touchscreen of the light check? Just wondering what it looks like and where its located.
 
In the EVIC under the trailer menu, scroll to the side and it gives you an option for light check. Enable it, and it will begin to cycle through left turn, right turn, brake, maybe reverse. It will continue to cycle so you can walk around and check all the lights. I'm sure it times out, but I haven't left it on long enough to find out. Obviously you have to be in park for it to work as well.

No pictures, as I'm at work right now, but it's just words on a screen.
 
I’ve tried it once on my box trailer, and I don’t think it has a time out as I had to manually turn it off. It does include the reverse lights on the trailer too, if equipped. It’s a handy feature, although I don’t know if always remember to use it. I normally turn flashers and lights on to check trailer lights.
 
I wonder if this will be one of those things you can AlphaOBD onto a 19-20 by telling it you have a 21 BCM.
 
Hard to say unless/until we see an update to support 21 BCM.

There are diags showing in Alfa to turn on each of those lights... but i haven't seen any option for the CSM piece that would need to be there. I do see some trailer lamp relay control options but unsure what those do.
 
OTA updates are for Tesla's and fancy market cars.

New features are incentives to trade in and buy the new one for bread and butter vehicles. I don't see the big 3 doing OTAs on HD trucks any time soon.
 
I got a chance to check out a '21 Limited Mega Cab yesterday, so I saw the trailer light check under trailer settings in the gauge cluster screen. Wow, I was in love with that truck. Never liked the mega cab before either. They had a manager's demo 2020 Limited Mega Cab with a leveling kit on 22s. Very nice look! This 2021 felt very refined and the steering (adaptive) was excellent compared to the adaptive steering on my 2020. I did think that the AISIN shifted a lot smoother as well.
 
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Pages 118, 256 & 257 in the owner's manual discusses the "Trailer Light Check" functions. Time out is 5 minutes if you do nothing after it is activated.
 
I didn’t know this feature was there until reading this thread. Tested it out today on the utility trailer and it worked great. When I got in and hit the brakes it stopped.
 
I didn’t know this feature was there until reading this thread. Tested it out today on the utility trailer and it worked great. When I got in and hit the brakes it stopped.
I did the same last weekend... Another new feature I didn't know I had. Worked great on my 5th wheel.
 
I am getting an error “unavailable conditions not met” when I Go to Trailer light check, what am I missing?
 
I am getting an error “unavailable conditions not met” when I Go to Trailer light check, what am I missing?
I know you have to be parked with your foot off the brake I believe... I've seen that message before but can always get it to do the light check if I want it to. Can't remember exactly how... I'll have to check it out tomorrow.
 
Does the manual say 5 minutes?

The setting in the BCM is number of cycles.
From what I see on page 259 of the online owner's manual it states :
"When activated the feature will enable all of the
exterior lights sequentially for up to five minutes
for time to walk around and verify functionality."
 
I just recently swapped a 2021 cluster into my 2019, in the pursuit of getting off-road pages, trailer Blindspot, and this trailer light check.

I have all features enabled in alfaobd, and off-road pages as well as trailer blind spot now display and mostly work.

Trailer light check is still missing... Is the menu option only available when a 7 pin trailer is hooked up?
 
I just recently swapped a 2021 cluster into my 2019, in the pursuit of getting off-road pages, trailer Blindspot, and this trailer light check.

I have all features enabled in alfaobd, and off-road pages as well as trailer blind spot now display and mostly work.

Trailer light check is still missing... Is the menu option only available when a 7 pin trailer is hooked up?
My '22 will do the light check with no trailer hooked up
 
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