IG1 No2 circuit

Anyone happen to have a wire schematic for the IG1 No2 circuit for a 2021 Tacoma? I am up in Alaska and drove the dalton highway yesterday. I smoked a huge pothole and blew the fuse. Keeps blowing them so need to find what all this fuse powers so I can try to find the shorted wire. @caribe makaira maybe?

I have no climate controls, no outside temp reading, PCS malfunction and lane departure warning BUT I have adaptive cruise still so radar is still working for that. Thanks!!

 

These files are for a 2016, I don't have the specific ones for a 2021.

 

You are a saint!! That’s the list I was looking for. I have an aftermarket bumper on the truck and the BSM wires are tied up but full of junk. I wonder if the switch got turned on since it is stuffed back in the dash. Thank you kindly!

 

https://www.corsa-technic.com/item.php?item_id=1002
this be the opposite/mating connector so you don't get gunk on the exposed terminals

 

Well the BSM was still switched off. I cleaned the terminals and checked the tow harness since I have a 35 shoved in the spare spot. No chafing that I can see. Also pulled the 30a towing fuse. No luck.

 

I had mine blow from MESO puddle pods wire grounding out on my door metal. Apparently didn't route the wire well enough and wore through the jacket. It would blow the fuse when opening the driver door. Anything tied into your body ECU like that? Like to the dome light or other walk up lighting?

 

I unplugged the AC Mag Clutch relay, unplugged the seat heater and motor harnesses on both seats. Put a fuse in and it didn’t blow. Put the relay back in. Stayed on. Plugged in the passenger seat. Stayed on. Plugged in the drivers seat. Stayed on. Sooooo everything is connected again and working properly. Jumped a couple frost heaves already and no issues. Who the hell knows!

 

Since this has the possibility of happening again, I'd like to clear up a misunderstanding you have about the BSM. Power is supplied to the 2 BSM module connectors regardless of the BSM dash switch position. Also supplied is the CAN to the left module and some inter-module CAN too, but this last one would not matter if power were removed from the circuits or in your case the BSM modules completely removed. Just adding this last statement for other people to more properly understand their truck.

The power to the BCMs could be interrupted at EB3 inside the engine compartment fuse box. See attached file. The CAN I don't have time to investigate at this time. You may also notice from the schematic the CAN to the rear of the vehicle also goes through the Engine Bay Fuse Box. IIRC there was more that this circuit was doing than just the BSM CAN - beware. There is a 2025 or late 2024 thread where someone added the BSM to their vehicle and they had to run the CAN back to the rear of the truck and then back to the front to make a complete bus there and back, IIRC. Suggest that thread for the BSM CAN delete.

Of course, you could just clean up the now corroded connectors and cap the BSM connectors as previously suggested. However, if you take that route you will need 10 plugs (not seals) for each mating connector from Corsa. Otherwise, you will still have a route for water to enter the connector. While you are on your trip this option most likely is not available to you.

Also, IIRC this CAN that feeds the BSM is one of four CAN busses on the truck and is not vital to the basic operation. I.e. the other CAN connected modules do not cause a complete lack of drivability.

 

You hit the nail on the head I believe. The fuse blew again after some rain here so I found a Napa in Dawson City to get some contact cleaner. Cleaned the BSM connectors and wrapped them in a baggie and electrical tape for the time being. Fuse didn’t blow and no rain in the forecast for a while. I’m sure the dempster will still be a muddy mess so I’ll keep an eye on that. Ordered the pigtail connectors so they will be at home waiting for me when I get there.

As for the CAN this circuit supports, completely drivable other than no HVAC.

 

If you didn't order the plugs for the connectors, you can try some sealant too. Just don't for a moment think the seals supplied are enough - they are not.

I wouldn't want to drive in Alaska in the summertime without closed windows and AC to keep those flies at bay.

What bumper manufacturer?

 

That’s the plan with the connectors. RTV to seal it the best I can. Luckily the mosquitoes haven’t been bad at all yet but it’s supposed to be heating up this week so we shall see!

Ironman bumper.

 

https://www.corsa-technic.com/item.php?item_id=1055

Plug for connector (no rtv)

 

Well found out that isn’t going to work on the passenger side. Found the issue…after smelling burnt electronics and sizzling after putting a fuse in. Just cut the plug off since it’s toast and folded the pig tails over with heat shrink.

 

That’s too bad.

 

Well there's your issue