Those are great tools, but you really shouldn't leave anything plugged into the OBD port. It's designed as a diagnostic port. If the item that's plugged in malfunctions or overheats, you could do serious damage to the vehicle. ECM's, BCM's, etc. are NOT cheap to replace!

 

To each their own…for me, I’ve been using SC2 since 2006 with zero issues. I have it on three of our company trucks, never had the cables unplugged on any of them since 2006-2008, and zero issues.

As if the SC3, you are correct. The SC3 generates heat unlike the SC2 thus I’ll be unplugging it when not in use.

 

I have version 4.53 and I can set the protocol to CANLF, but how to you set the WWHOBD to on? I can't find that setting under setup.

 

So through Google AI I found out that the 2026 uses J1979-2 / OBDonUDS for the OBD2 connection which the SG2 would need a firmware update. I've sent an email inquiry to Linear Logic to see if this is possible.

Edit:
Received response from Linear Logic:

Unfortunately the ScanGauge2 unit cannot be upgraded to work on a 2026 Honda Passport. The 2026 Honda Passport is using the WWHOBD protocol while a 2019 Honda Passport is using the OBDII protocol. The ScanGauge2 unit will not be able to connect to the WWHOBD protocol. The ScanGauge2 circuit board cannot handle the WWHOBD protocol requirements.

 

Thank you Gray_Beard for running the traps on the ScanGauge 2 as your due diligence will save other MY 2026 Passport owners from the hassle.

I've changed the title of this thread so anyone searching for into about the ScanGauge 2 for MY 2026 should be able to find your valuable information quickly. Again, thank you as it's folks like you who help make the forum better for all of us.

 

Hey Evergreen, like you I always had my SG2 plugged in. I bought mine in 2019 and it stayed plugged into my PPE till I traded it in April of this year. In fact I've left it in a couple of times when I brought it in for service and no one said anything about it. You mentioned the SG3 generates heat, so you unplug it when not in use. Is this the case even when the vehicle is turned off? Is the SG3 drawing current all the time when plugged in? And just how warm is the SG3 getting? Like cell phone battery charging kind of warm or different than that.
Curious because I miss not having a SG and hoping maybe during Amazon Prime deal days the SG3 might be on sale.

 

Back in 2024 I had the problem when it melted a 3D printed storage bin in our previous Passport.

https://www.passportforums.com/threads/scangauge-iii.11528/page-2

To answer your question concerning heat of the new unit I just purchased, I installed the SG factory suction cup mount on the windshield by the Bose speaker but couldn’t tell if it was the unit or the Texas heat. So, I moved it down inside to the right of the charging pad by turning the mount upside down and putting the suck up on the top of the cubbie under the USB ports. So far, the heat has been negligible like a warm cell phone when running and no heat in the morning however I only left it plugged in one night for a few hours to test it but will still unplug it from the back (as opposed from the OBD port) every night just to be safe.

 

A quick follow up…I took my handheld infrared thermo gun when we went to town today, and the hottest reading I got off the SG3 was 81 degrees. Temps of the unit averaged 79 degrees throughout the trip. The hottest reading was obtained from the top vents on the back of the SG3. It’s possible the unit I had previously in 2024 was defective…the good thing is I was able to return that unit back then as Linear Logic stands behind their products.

That temps I got in this new unit were with the SG3 mounted per the pics below.

 

Well that's excellent news! And BTW, having the mount below the USB ports looks pretty good!
LOL, it's been cloudy all day here in SW Florida and it's still 88 degrees in the shade! Yeah, I would agree that you had a defective unit in 2024. Linear Logic is a stand up company. Now just waiting to see a decent sale.