Hello, if you have the ABS light come on, there should be a diagnostic trouble code stored in the ABS module (computer), so don't erase anything because it will be the only information you will have right now as to what may have happened. Erasing the memory or codes might restore its function, but we will have no idea where to start checking. You won't be able to scan the ABS module with a basic scan tool, it will need to be a scan tool that can scan all the modules in the vehicle. Not just the Engine computer. If you can get a full system scan done on the vehicle, there will most likely be some codes to give diagnostic directions. Because this vehicle has traction control and Skid control incorporated into ABS system, you will need to get a scan tool that can scan the ABS, but it would be better to get a full system scan done just in case there are codes stored in other modules that are just not showing a caution light right now such as the Transmission module. Obviously there has been some kind of failure, corrupted data, or communications fault detected. I recommend figuring out what is happening before you attempt to tow anything. You don't want to lose some function especially with a heavy load like that.
These vehicles can have load sensors on the Brake pedal switch, downhill braking assist, steering sensor, yaw rate sensor, etc. So, it most likely was something to do with the load you were trying to tow that triggered a code. Interesting that the transmission locked up, that might be a security type activation as well.
I don't see any technical service bulletins on anything like this either.
You can start by checking these fuses, just don't pull any out, because it may erase codes stored in the engine computer which looks like it also controls the Transmission. I would just check these with an Automotive 12v test light hooked to battery negative, if they are Maxi fuses you can see into them and see if they are blown.
And have you had any work done lately, even just tires changed?
One other thing, is there an Information Display in your vehicle and if so, is there anything besides a master alarm and ABS light?
After taking a look at the wiring diagrams here are a few other fuses to check, and what kind of repair did you need to do to the trailer lights assembly?
Fuses to check FL Main, ALT 140amp, TAIL 15amp, ECU IG 7.5amp, STOP 10amp, TOWING 30amp.
The FL MAIN is a fusible link located near the battery, these are not regular fuses, it is a section of wire that is designed to burn just like a fuse when there is excessive current flow. This one appears to be hooked directly to the battery (5th diagram).
Images (Click to enlarge)
Sunday, June 19th, 2022 AT 10:43 AM